STRATIGRAPHIC SIGNIFICANCE OF CRINOIDAL
COLUMNS OF THE TRAVERSE OF MICHIGAN

by
WILLIAM EDWARD DAVIES

A THESIS
S u b m i t t e d t o t h e G r a d u a te S c h o o l o f M ic h ig a n
S t a t e C o l l e g e o f A g r i c u l t u r e a n d A p p lie d
S c ie n ce i n p a r t i a l f u l f i l m e n t o f th e
re q u ire m e n ts f o r th e d egree of
MASTER OF SCIENCE

D e p a r tm e n t o f G eology
1941

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CONTENTS
Page
In tro d u c tio n

1

P u r p o s e o f S tu d y

2

S tra tig ra p h y

2

M ethod o f P r e p a r a t i o n

5

C o n clu sio n s

8

A cknow ledgm ents

10

B ib lio g ra p h y

11

D e s c r i p t i o n o f C o lu m n a ls

12

134219

STRATIGRAPHIC SIGNIFICANCE OF CRINOIDAL
COLUMNS OF THE TRAVERSE OF MICHIGAN

INTRODUCTION
C r i n o i d a l r e m a i n s , a l t h o u g h v e r y common a s f o s s i l s i n many
f o r m a t i o n s , h a v e seld o m b e e n u s e d a s in d e x o r m a rk e r f o s s i l s .
P r o b a b l y m ost g e o l o g i s t s h av e r e a l i z e d t h e h o p e l e s s n e s s o f a s s o c ­
i a t i n g a n i n d i v i d u a l f r a g m e n t o f a c r i n o i d w i t h t h e w hole c r i n o i d
o f w h ic h i t was once a p a r t .

As a r e s u l t m o st c r i n o i d a l r e m a in s

h a v e b e e n lumped t o g e t h e r i n t h a t f a m i l i a r t e r m " C r i n o i d e a " .
O nly a few a r t i c l e s h av e a p p e a r e d i n p r i n t i n w h ic h t h e
c l a s s i f i c a t i o n o f c r i n o i d a l f r a g m e n t s h a s b e e n d i s c u s s e d and no
p r e v i o u s a t t e m p t h a s b e e n made t o e v a l u a t e t h e d e t a i l e d s t r a t i g r a p h i c s i g n i f i c a n c e o f c r i n o i d c o lu m n s .

Moore (1 9 3 8 ) l a i d down

th e p r i n c i p l e s of c l a s s i f i c a t i o n of fra g m e n ta l c r in o id re m a in s.
I n t h e T r a v e r s e g r o u p o f n o r t h e r n M ic h ig a n t h e r e a r e a number
o f i n t e r b e d d e d l i m e s t o n e s an d s h a l e s i n w h ic h c r i n o i d a l f r a g m e n t s
a r e f a i r l y common.
have r e c e iv e d l i t t l e

To d a t e t h e c r i n o i d colum ns o f t h e T r a v e r s e
a tte n tio n .

The p r e s e n t s t u d y i s c o n c e r n e d

w i t h t h e p o s s i b i l i t y o f u s i n g t h e c o lu m n a ls t o d i f f e r e n t i a t e t h e
v a rio u s fo rm a tio n s o f th e group.
The m a t e r i a l on w h ic h t h e i n v e s t i g a t i o n i s b a s e d was o b t a i n e d
b y s t u d e n t s an d i n s t r u c t o r s o f t h e D e p a rtm e n t o f G eo log y o f M ic h ig a n
S t k t e C o l l e g e on num erous f i e l d t r i p s t o t h e o u t c r o p s o f t h e T r a v ­
e r s e i n t h e n o r t h e r n p a r t o f t h e Lower P e n i n s u l a o f M ic h i g a n .

2.
Some s p e c im e n s w e re a l s o o b t a i n e d fro m w e l l s a m p l e s ,

PURPOSE OF STUDY
A lth o u g h f r a g m e n t a r y c r i n o i d a l r e m a in s a r e n o t c o n s i d e r e d
t o be w o r th y o f t h e s t r a t i g r a p h e r * s a t t e n t i o n , a n d i n f a u n a l
l i s t s a r e g r o u p e d u n d e r t h e s i n g l e t e r m " C r i n o i d e a , i n d e t . " , an
a t t e m p t i s made i n t h e p r e s e n t s t u d y t o e v a l u a t e t h e i r i m p o r t a n c e .
E v en w i t h b r i e f e x a m i n a t i o n f r a g m e n t a r y c r i n o i d a l m a t e r i a l c an
e a s i l y be s e p a r a t e d i n t o a r t i f i c i a l g r o u p s .

W ith t h i s i n mind

t h e c r i n o i d c o lu r a n a ls o f t h e T r a v e r s e g ro u p h a v e b e e n c l a s s i f i e d
a n d an a t t e m p t h a s b e e n made t o e v a l u a t e t h e s t r a t i g r a p h i c i m p o r t ­
ance o f such re m a in s.
O nly c r i n o i d colum ns a r e c o n s i d e r e d i n t h i s s t u d y f o r t h e y
a r e t h e m ost a b u n d a n t an d w i d e s p r e a d c r i n o i d a l r e m a in s i n t h e
T r a v e r s e g r o u p and h e n c e h a v e t h e g r e a t e s t s t r a t i g r a p h i c v a l u e .
M o o r e 's c l a s s i f i c a t i o n h a s n o t b e e n f o l l o w e d r i g i d l y i n t h i s
stu d y .

A s e r i e s o f l e t t e r s a n d num bers i n s t e a d o f names a r e u s e d

to d e s ig n a te th e v a rio u s co lu m n a ls,
STRATIGRAPHY
P l a t e IV a n d t h e b r i e f d e s c r i p t i o n s l i s t e d b e lo w s e r v e a s a
summary o f t h e s t r a t i g r a p h y o f t h e T r a v e r s e g ro u p i n n o r t h e r n
M ic h i g a n ,
A lp e n a A re a
SQUAW BAY LIMESTONE:

( W a r th in a n d C ooper)

Brown l i m e s t o n e , d o l o m i t i c i n some p a r t s .

C o n t a i n s S t y l i o l i n a a n d u p p e r D e v o n ian g o n i a t i t e s .

T h i c k n e s s 12 f e e t .

3
PARTRIDGE POINT FORMATION:

G rey an d b l u i s h a r g i l l a c e o u s

l im e s t o n e s , and g re y c a lc a re o u s sh a le s*
r e m a in s n u m e ro u s .

B l a s t o i d an d c r i n o i d

Known t h i c k n e s s 14 f e e t *

POTTER FARM FORMATION:

B lue t o g r e y s h a l e s , an d l o c a l i n t e r ­

bedded c r i n o i d a l , s u b lith o g ra p h ic or a r g illa c e o u s lim e s to n e s .
C v l i n d r o p h v l l u m a b u n d a n t . 36 f e e t maximum t h i c k n e s s .
NORWAY POINT FORMATION:

Brown a n d g r e y l i m e s t o n e s g r a d i n g

u p w ard i n t o a r g i l l a c e o u s an d c a l c a r e o u s c l a y .
u l o s u s a n d C ry p h a e u s b o o t h i .
ALPENA LIMESTONE:
c h e r ty n ear th e to p .

S o i r i f e r c f* g r a n ­

46 f e e t .

M a s s iv e g r e y and brow n g r a n u l a r l i m e s t o n e ,
C o r a l r e e f s common a n d e x t e n s i v e .

o h i c k n e s s a b o u t 125 f e e t .

Maximum

The Dock S t r e e t c l a y i s a l o c a l g r e y

c l a y f a c i e s o f t h e U pper A lp e n a .
KILLIANS LIMESTONE:
s h a le .

Dark g r e y t o b l a c k l i m e s t o n e a n d b l a c k

T h i s i s t h e to p m o s t zone o f a s e r i e s o f b l a c k s h a l e s and

l i m e s t o n e s t h a t i n t e r f i n g e r w i t h t h e Genshaw.

I t i s p ro b a b ly

a b l a c k f a c i e s o f t h e G enshaw .
GENSHAW FORMATION:

T h in g re y lim e s to n e s a l t e r n a t i n g w ith g rey

c a l c a r e o u s s h a l e s c o n t a i n i n g a l a r g e fo rm o f A tr y p a and G y p id u la
ro m in g e ri.

Maximum t h i c k n e s s o f Genshaw a n d K i l l i a n s , 75 f e e t .

FERRON POINT SHAIE:

G re en t o b l u i s h c l a y s , i n x e r b e d d e d w i t h

a r g illa c e o u s lim e s to n e s , very f o s s i l i f e r o u s .
ROCKPORT LIMESTONE:
b itu m in o u s m a t e r i a l .

T h i c k n e s s a b o u t 35 f e e t .

B lu e t o d a r k g r e y l i m e s t o n e w i t h much

Numerous f o s s i l s .

T h i c k n e s s a b o u t 40 f e e t .

4.
BELL SHALL:

S o f t, dark g re y to b la c k a r g i l l a c e o u s s h a le ,

a b u n d a n tly f o s s i l i f e r o u s .

A f to n A rea
The f o r m a t i o n s i n t h i s a r e a a r e s i m i l a r t o t h o s e a r o u n d
A lp e n a e x c e p t f o r t h e b e d s b e tw e e n t h e K i l l i a n s and t h e P o t t e r
Farm*

T h i s i n t e r v a l a t A f to n i s made up o f b eds p r o v i s i o n a l l y

known a s t h e M a r v in , E l l i s an d Beebe i n t h e u p p e r p a r t an d t h e
A f t o n b e d s b e lo w ( K e l l y , 1940)«

The u p p e r b e d s c o n s i s t o f d a r k

6 re y t o b la c k lim e s to n e (M arv in ),

m a ssiv e , g rey c r y s t a l l i n e

l i m e s t o n e ( E l l i s ) , a n d g r e y l i m e s t o n e s , somewhat s i l i c e o u s
and green g rey sh a le (B e eb e )•

The A f to n i s a d e n s e t o f i n e l y

g r a n u l a r , l i g h t g r e y l i m e s t o n e a b o u t 50 f e e t x h i c k .

P e t o s k e y A re a ( P o h l)
PETOSKEY FORMATION:

B uff g re y t o b la c k lim e s to n e ,

occas­

i o n a l l y b i t u m i n o u s , i n t e r b e d d e d w i t h g r e y t o b l a c k s h a le *
CHARLEVOIX LIMESTONE:

G r a n u l a r t o m a s s iv e g r e y and brown

lim e sto n e •
GRAVEL POINT FORMATION:
a b r o w n is h t i n g e .

Dark g r e y t o b l a c k l i m e s t o n e w i t h

Some b l u i s h g r e y s h a l e n e a r t h e t o p .

These c o rre sp o n d i n age to th e A lp e n a - P a rtrid g e P o in t i n t e r v a l
o f t h e A lp e n a a r e a a n d t h e M a rv in -B e e b e i n t e r v a l o f t h e A f to n a r e a .
The lo w e r h a l f o f t h e T r a v e r s e i s c o n c e a l e d i n t h e P e t o s k e y a r e a .

PLATE

IV

C olum nar s e c t i o n s o f t h e T r a v e r s e g r o u p , n o r t h e r n p a r t o f
t h e Lower P e n i n s u l a o f M i c h i g a n .

M o d if ie d fr o m K e l l y ( 1 9 4 0 ) .

£

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5,
METHOD OF PREPARATION
The m a j o r i t y o f t h e c o lu m n a ls ex am in ed w ere f r e e fr o m s u r r o u n d ­
in g ro c k and needed l i t t l e

p r e p a r a t i o n bey o n d c l e a n i n g .

o c cu rred in rock m a trix re q u ir e d s p e c ia l p r e p a r a tio n .

T ho se t h a t
The a r r a n g e ­

m en t a n d t h i c k n e s s o f s u c h c o lu m n a ls w ere o b t a i n e d b y m aking l o n g ­
i t u d i n a l p o l i s h e d s e c t i o n s o f t h e s te m s embedded i n t h e ro c k #
a r t i c u l a t e s u r f a c e p ro v e d r a t h e r d i f f i c u l t t o o b t a i n #

The

E tch in g

p r o v e d u n s u c c e s s f u l f o r i t w ould d e s t r o y one f e a t u r e o f t h e s u r f a c e
w h ile b r in g in g o ut a n o th er#
to th e a r tic u la te

su rface.

P o l i s h e d s e c t i o n s w e re made p a r a l l e l
In th e case of a f l a t a r t i c u l a t e su rfa ce

t h e f a c e was g ro u n d down u n t i l i t had r e a c h e d t h e l e v e l o f a n
a rtic u la te

s u r f a c e and t h e n p o l i s h e d #

w e re e a s i l y o b s e v e d t h e n #

The d e t a i l s o f t h e s u r f a c e

I n th e c ase o f a concave a r t i c u l a t e

s u r f a c e i t was n e c e s s a r y t o g r i n d t h e s u r f a c e down by s u c c e s s i v e
s t a g e s and n o t e t h e c h a n g e s t h a t t o o k p l a c e i n t h e d e t a i l s on t h e
su rface.

On t h e s p e c im e n s t h a t w ere f r e e o f s u r r o u n d i n g r o c k i t

was fo u n d n e c e s s a r y t o g r i n d and p o l i s h one a r t i c u l a t e s u r f a c e i n
o r d e r t o be c e r t a i n o f t h e s h a p e o f t h e lumen#
MORPHOLOGIC CHARACTER OF CRINOID COLUMNALS
C r i n o i d c o lum ns a r e made up o f d i s c - l i k e o r k e g - s h a p e d s e g m e n ts known a s c o l u m n a l s .

The t o p and b o tto m s u r f a c e s

(a ^ ic u l-

a t e s u r f a c e s ) a r e g e n e r a l l y f l a t o r s l i g h t l y d e p re ss e d and a r e
p i e r c e d a t t h e c e n t e r by a c a n a l (lu m en ) whose a x i s i s p e r p e n d ­
i c u l a r to th e a r t i c u l a t e s u rfa c e .
M ost c o lu m n a ls a r e c i r c u l a r i n c r o s s s e c t i o n a l t h o u g h fo rm s

6
o c c a s i o n a l l y o c c u r i n w h ic h t h e s h a p e i s e l l i p t i c a l ,
q u a d ra n g u lar o r s t e l l a t e #

p e n tag o n a l,

I n t h e colum n o f a s i n g l e i n d i v i d u a l

t h e c o lu m n a ls a r e u s u a l l y o f t h e same c r o s s s e c t i o n a l o u t l i n e b u t
i n d i v i d u a l c o lu m n a ls v a r y i n s i z e #

Those d i s c s p o s s e s s i n g n o d e s

( n o d a l d i s c s ) a r e g e n e r a l l y w i d e r and t h i c k e r t h a n t h e n o n - n o d a l
seg m e n ts#

I n t h e colum n t h e a r r a n g e m e n t o f n o d a l a n d n o n - n o d a l

c o lu m n a ls i s u n if o r m and s e r v e a s a f e a t u r e i n d i s t i n g u i s h i n g
v a r i o u s c o lu m n s .
The d i a m e t e r o f a c o lu m n a l i s c o n s i d e r e d t o be t h e maximum
d i s t a n c e a c r o s s a c o lu m n a l on t h e a r t i c u l a t e s u r f a c e m e a s u re d
t h r o u g h t h e lumen#

The t h i c k n e s s i s t h e maximum t h i c k n e s s m eas­

u r e d p a r a l l e l t o t h e a x i s o f t h e lum en .
The a r t i c u l a t e

s u r f a c e s o f t h e c o lu m n a ls a r e g r i l l e d by f i n e

r a d i a t i n g r i d g e s w h ic h a r e known a s c r e n e l l a e .

M ost c r e n e l l a e

a r e s i n g l e , s t r a i g h t r i d g e s i n w hich c a s e t h e y a r e t e r m e d s i m p l e .
O c c a s i o n a l l y t h e c r e n e l l a e d i v i d e on a p p r o a c h i n g t h e p e r i p h e r y #
C re n e lla e of t h i s ty p e a re d e sig n a te d as b i f u r c a tin g c r e n e l l a e .
A long t h e

edge o f t h e c o lu m n a l t h e number o f c r e n e l l a e i s o f t e n

i n c r e a s e d by t h e a d d i t i o n o f s h o r t c r e n e l l a e .
known a s i m p l a n t e d c r e n e l l a e .

Such c r e n e l l a e a r e

I n m ost c o lu m n a ls t h e i m p l a n t e d

c r e n e l l a e o c c u r on one a r t i c u l a t e s u r f a c e w h i l e on t h e o t h e r
su rface b ifu r c a tin g c re n e lla e occur.

When t h e two s u r f a c e s a r e

i n c o n t a c t t h e i m p l a n t e d c r e n e l l a e f i t i n t o t h e g r o o v e s fo rm ed
by t h e b i f u r c a t i n g c r e n e l l a e .

The p r e s e n c e o f i m p l a n t e d c r e n e l l a e ,

h o w e v e r , d o e s n o t im p ly t h e p r e s e n c e o f o p p o s i t e b i f u r c a t i n g o n e s

7
a s o f t e n d i s c s a r e fo u n d w h ic h h a v e i m p l a n t e d c r e n e l l a e on b o t h
a r t i c u l a t e s u rfa c e s w ith o u t co rresp o n d in g b if u r c a t i n g c re n e lla e #
The zone b e tw e e n t h e lumen and t h e c r e n e l l a e i s d e s i g n a t e d
as th e c e n tr a l a r e a .

I n many c o lu m n a ls t h i s a r e a i s m i s s i n g a s

t h e c r e n e l l a e e x t e n d t o t h e lu m e n .

The c e n t r a l a r e a i s g e n e r a l l y

sm ooth a n d f l a t o r s l i g h t l y c o n c a v e .
M ost lum ens w ere f o u n d t o be c i r c u l a r i n o u t l i n e .
v e r y common fo rm was t h e c i n q u e f o i l o r p e n t a p e t a l o i d .

A n o th e r
O th e r l e s s

common o u t l i n e s w ere p e n t a g o n a l , f i v e p o i n t e d s t a r s , e l l i p t i c a l ,
o r m ere s l i t s .

The d i a m e t r a l r a t i o o f t h e lumen i s a l s o a n i m p o r t ­

a n t f e a t u r e t o be n o t e d i n c l a s s i f i c a t i o n .

I n many colum ns t h e

lumen i s w i d e r a t t h e a r t i c u l a t e s u r f a c e t h a n a t t h e c e n t e r o f
th e d is c .

I n r a r e c a s e s t h e lumen i s o f d i f f e r e n t sh ape i n d i f f ­

e r e n t p a r t s of th e co lu m n al.
The p e r i p h e r y o r n o n - a r t i c u l a t e s u r f a c e i s g e n e r a l l y s m o o th .
I n p r o f i l e i t i s p la n e , co ncave, convex.

The m ost common

m o d i f i c a t i o n s o f t h i s s u r f a c e a r e k e e l s , r i d g e s and f l a n g e s .
More r a r e l y t u b e r c l e s , s p i n e s o r g r a n u l e s o c c u r on t h e p e r i p h e r y *

TABLE

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STRATIGRAPHIC OCCURRENCE OF CRINOID COLOURAL3 IN

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CC1A
CC1B
CC1C
CC1D
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CC1F

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CC2A
CC2B
CC2C
CC2D
CC2E
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CONCLUSIONS
T h i s s t u d y i s b a s e d on o v e r 1000 s p e c im e n s o b t a i n e d fro m
26 l o c a l i t i e s , r e p r e s e n t i n g 11 g e o l o g i c h o r i z o n s *
c o l l e c t i o n 65 s u b s e c t i o n s w ere d i s t i n g u i s h e d .
w e re e q u a l l y r e p r e s e n t e d .

From t h e

Not a l l l o c a l i t i e s

I n some l o c a l i t i e s o v e r 100 s p e c im e n s

w e re o b t a i n e d w h i l e f r o m o t h e r s o n l y a s i n g l e s p ec im e n was a v a i l ­
a b l e f o r e x a m i n a tio n *

Many o f t h e s p e c im e n s w ere i n m a t e r i a l

t h a t had b e e n o b t a i n e d by t h e c o l l e c t o r f o r o t h e r p u r p o s e s .
L o c a l i t i e s fro m w h ic h su c h c o l l e c t i o n s w ere made a r e t h e r e f o r e
p o o rly re p re s e n te d .
The c o n c l u s i o n s r e a c h e d c a n o n ly be t e n t a t i v e .

More t h o r o u g h

c o l l e c t i n g a t e a c h l o c a l i t y w i l l make p o s s i b l e a d e f i n i t e c o n c l u s i o n
a s t o t h e s t r a t i g r a p h i c v a l u e o f e a c h t y p e o f c o lu m n a l.
From t h e m a t e r i a l c l a s s i f i e d t h e r e i s a s t r o n g s u g g e s t i o n
t h a t c e r t a i n c r i n o i d colum ns c an be u s e d a s i n d e x f o s s i l s .

The

p o s s i b i l i t y o f c o r r e l a t i o n b e tw e e n t h e A lp e n a - A f to n a r e a and t h e
P e t o s k e y a r e a was a l s o i n d i c a t e d by t h e few c o lu m n a ls t h a t w ere
c l a s s i f i e d fro m t h e P e t o s k e y a r e a .
The c o lu m n a ls fro m t h e P e t o s k e y a r e a showed many new fo rm s
t h a t w e re d i s t i n c t fro m t h o s e o f t h e A f to n - A lp e n a a r e a .

T h ese

fo rm s w e re n o t c l a s s i f i e d a s t h e y w ere beyond t h e s c o p e o f t h e
s tu d y *

O nly t h e u p p e r h a l f o f t h e T r a v e r s e i s e x p o s e d a ro u n d

P e to sk ey .

I n t h e A f to n - A lp e n a a r e a t h e lo w e r h a l f i s b e s t e x ­

p o s e d , t h e u p p e r h a l f b e i n g m a in ly c o n c e a l e d .

The d i f f e r e n c e

i n h o r i z o n fro m w hich t h e c o lu m n a ls o f t h e two a r e a s w ere o b t a i n e d
w ould a c c o u n t f o r t h e many new fo rm s i n t h e P e t o s k e y a r e a .

9

L i m i t a t i o n s upon t h e work may be im p o se d a s f u r t h e r s t u d y
i s c a rrie d on.

F o r exam ples

I f c e r t a i n c o lu m n a ls w i t h o u t a

c e n tr a l area lik e C - C - 2 - A ( P l .

I , f i g . 8) p ro v e t o be a p a r t

o f t h e colum n o f t h e same s p e c i e s a s t h a t w h ic h i n a n o t h e r p a r t
o f t h e colum n p o s s e s s e s a c e n t r a l a r e a a s t y p i f i e d b y C - C - 3 - A
( P I * I , f i g . 10) t h e n t h e v a l u e a s a g u i d e f o s s i l w i l l d i s a p p e a r ,
s i n c e C - C - 3 - A h a s an e x t e n s i v e s t r a t i g r a p h i c ra n g e *
The t e s t o f w h e th e r t h e s u b s e c t i o n s a r e e q u i v a l e n t t o t r u e
s p e c ie s w ith d e f in ite
in te n se c o lle c tin g .

s t r a t i g r a p h i c r a n g e s w i l l come w i t h f u r t h e r
The c o l l e c t i n g w h ic h h a s b e e n done so f a r h a s

n o t b e e n s e l e c t i v e and u n l e s s c o i n c i d e n c e be c a l l e d upon i t seems
d i f f i c u l t t o a c c o u n t f o r t h e p r e s e n c e o f c o lu m n a ls o f one s u b s e c t ­
i o n a n d t h e a b s e n c e o f c o lu m n a ls o f a n o t h e r s u b s e c t i o n i n a h o r i z o n
i f t h e y w ere b o t h p a r t s o f t h e same co lu m n .
C o n v e r s e l y , t h e r e i s no i m p l i c a t i o n t h a t b e c a u s e one s u b s e c t ­
i o n o c c u r s i n b e d s s t r a t i g r a p h i c a l l y f a r a p a r t , t h a t t h e same s p e c i e s
i s re p re se n te d .
m o rp h y .

Such an o c c u r r e n c e may b e a n exam ple o f homeo-

From t h e s t r a t i g r a p h e r ' s v i e w p o i n t , h o w e v e r, su c h r e o c c u r r ­

e n c e s o f a s u b s e c t i o n d e t r a c t s fr o m i t s v a l u e i n c o r r e l a t i o n .

10
ACKNOWLEDGMENTS
The a u t h o r w i s h e s t o e x p r e s s h i s a p p r e c i a t i o n f o r t h e a i d
g i v e n by D o c to r W. A. K e l l y d u r i n g t h e w r i t i n g o f t h i s t h e s i s ,
a n d t o D o c to r S . G. B e r g q u i s t and Mr* J . A. Young f o r r e a d i n g
t h e m a n u s c r i p t an d f o r t h e h e l p f u l s u g g e s t i o n s t h e y h a v e g iv e n *
To W arren J . A n d e rso n a n d o t h e r s t u d e n t s

o f t h e D e p a rtm e n t o f

G eo lo g y o f M ic h ig a n S i f t t e C o l l e g e

t h e w r i t e r i s i n d e b t f o r many

c r i n o i d r e m a in s t h a t t h e y s e c u r e d

i n t h e s p r i n g o f 1941 a n d w h ic h

w e re i n c o r p o r a t e d i n t h i s s t u d y .

XI

BIBLIOGRAPHY
1930
P o h l,

E . R .,

i n M ic h i g a n ,

The M id d le s D e v o n ian T r a v e r s e Group o f r o c k s
P ro c .,

U. S. N at*

M u s .,

v o l. 76,

pp 1 - 3 4 .

1935
W a r t h i n , A . S . an d

C ooper,

t h e M ic h ig a n D e v o n ia n .

G. A . ,

J o u r.,

New f o r m a t i o n names i n

^ a s h . A cad . S c i * , v o l . 2 5 ,

p p . 524 - 5 2 6 .
1938
M oore,

R. C . ,

The use o f f r a g m e n t a r y c r i n o i d a l r e m a in s i n

s t r a t i g r a p h i c p a le o n to lo g y .
S c i e n t i f i c L a b ., v o l. 33,

D e n iso n U n iv . B u l l . ,

Jo u r.

p p . 165 - 2 5 1 .

1940
K e l l y , W. A . ,

G u id e b o o k .

T e n th a n n u a l g e o l o g i c a l e x c u r s i o n ,

M ic h ig a n Academy o f S c i e n c e , A r t s and L e t t e r s t o A fton-Onow ay
d istric t.

12

DESCRIPTION OF COLUMNALS
M oore*s c l a s s i f i c a t i o n h a s n o t b e e n f o l l o w e d r i g i d l y i n t h i s
stu d y .

The b r o a d e r te r r a s u s e d by Moore h av e b e e n r e t a i n e d b u t

i n t h e s m a l l e r s u b d i v i s i o n s a s y s te m o f l e t t e r s and num bers h a s
b e e n s u b s t i t u t e d i n p l a c e o f n am es.

The c l a s s i f i c a t i o n u s e d i n

t h i s s t u d y d i v i d e s M oore*s s e c t i o n d e s i g n a t i o n i n t o s u b s e c t i o n s
i n o r d e r t o o b t a i n a more d e t a i l e d c l a s s i f i c a t i o n w h ic h i s n e c e s s ­
a r y i f t h e c o lu m n a ls a r e t o be o f s t r a t i g r a p h i c v a l u e .
I n t h i s s y s te m t h e f i r s t l e t t e r d e s i g n a t e s t h e c r o s s s e c t i o n ­
a l o u tlin e s

C

in d ic a te s a c i r c u l a r c ro ss s e c tio n , P a p e n ta ­

gonal cro ss s e c tio n .

The s e c o n d l e t t e r s i g n i f i e s t h e o u t l i n e o f

t h e lum en:

C i s a c i r c u l a r lu m e n , F a c i n q u e f o i l o n e , P a p e n t a ­

gonal one,

S a s lit-lik e

lu m e n .

The number and l a s t l e t t e r

com bine t o make up t h e s e c t i o n a n d s u b s e d t i o n i d e n t i f i c a t i o n .

D i v i s i o n CRINOSTYLI Moore (C o lu m n a ls )

M ain G roup CYCLOSTYLI Moore
A l l c o lu m n a ls t h a t o r e e s s e n t i a l l y c i r c u l a r i n o u t l i n e a r e
in c lu d e d i n t h i s gro u p .
Group CYCLOCYCLOPAE Moore
C y c l o s t y l i w h ic h p o s s e s s a c i r c u l a r lu m en .

S e c tio n C - C - 1

D a v ie s

C y c l o c y c l o p a e w i t h a s m a l l lumen w h ic h i s s u r r o u n d e d by a

13
t u b e - l i k e r i d g e and no c e n t r a l a r e a *

C - C - 1 - A
P la te I

S e c tio n ty p e C - C - 1 - A

D a v ie s

F ig u re 1.

C ir c u la r c ro ss sec tio n *

D ia m e te r 8 t o 10 mm,

A l t e r n a t e n o d o s e and n o n -n o d o s e d i s c s *

A n n u la te :

Nodose d i s c a b o u t 1 mm,

o h i c k , k e e l e d a n d a b o u t 0 , 5 mm, w id e r t h a n t h e n o n -n o d o s e d i s c .
N o n -n o d o se d i s c 1 ram* t h i c k ; p e r i p h e r y p l a n e and s m o o th .

A rtic ­

u l a t e s u r f a c e s l i g h t l y c o n c a v e , c e n t e r b e i n g d e p r e s s e d a b o u t 0*5
ium*

A r t i c u l a t e s u r f a c e g r i l l e d w i t h r a d i a t i n g c r e n e l l a e , m a in ly

s im p le ; b i f u r c a t i n g ones r a r e .

Lumen c i r c u l a r , a b o u t 0*2 mm. w id e ;

s u r r o u n d e d by a t u b e - l i k e r i d g e 0 . 2 mm. w i d e .

R id g e g r i l l e d w i t h

c re n e lla e •
R em ark s:

T h i s c o lu m n a l i s v e r y common i n t h e B e l l s h a l e a t t h e

R ockport Q uarry.
c la y .

I t a l s o o c c u r s s p a r i n g l y i n t h e Dock S t r e e t

A t y p e c l o s e l y r e s e m b l i n g t h i s fo rm o c c u r s a b u n d a n t l y i n

xhe P e t o s k e y f o r m a t i o n i n t h e w e s t e r n p a r t o f t h e S t a t e .
C - C - 1 - B
P la te I

D a v ie s

F ig u re 2

C irc u la r cross s e c tio n .

D ia m e te r 5 t o 8 mm.

A n n u la te:

C o lu m n a ls i n a s e r i e s o f fo u r*
1.

Nodose d i s c a b o u t 1 mm. t h i c k , k e e l e d ; a b o u t 0 . 5 mm.
w i d e r t h a n c o lu m n a ls 2 a n d 4 .

2.

N o n-n o d o se d i s c a b o u t 0 . 5 mm. t h i c k .

3.

N o n -n o d o se d i s c a b o u t 0 . 5 mm. t h i c k ; a b o u t 0 . 2 mm w id e r
t h a n c o lu m n a ls 2 a n d 4 .

4.

N o n -n o d o se d i s c a b o u t 0 . 5 mm. t h i c k .

14
A r t i c u l a t e s u r f a c e s l i g h t l y concave, c e n te r d e p re ss e d a b o u t 0 .5
mm.

Lumen c i r c u l a r , s u r r o u n d e d by a t u b e - l i k e r i d g e .

mm. w i d e .

R id g e s u r r o u n d i n g lumen g r i l l e d w i t h c r e n e l l a e .

u la te su rfa c e g r i l l e d w ith c r e n e lla e .
c r e n e l l a e common.
R em ark s:

Lumen 0 . 2
A rtic ­

B i f u r c a t i n g a n d im p l a n t e d

No c e n t r a l a r e a .

T h i s fo r m i s p r o b a b l y fro m t h e same s p e c i e s a s

C - C - l - A .

I t d i f f e r s from t h a t fo rm o n l y i n t h e a r r a n g e m e n t

of th e c o lu m n a ls.

C - C - l - B i s

common i n t h e B e l l s h a l e a t

th e R ockport Q uarry.
C - C - 1 - C
P la te I
C irc u la r cross s e c tio n .

D a v ie s

F ig u re 3.
D ia m e te r 5 t o 8 mm.

A lte rn a te

n o n -n o d o s e d i s c s 1 mm. t h i c k .

i s k e ele d

and i s 0.2, mm. w i d e r t h a n t h e o t h e r

su rfa ce s l i g h t l y concave.
C re n e lla e

A n n u la te:

E ach a l t e r n a t e d i s c
d isc .

A rtic u la te

G r ill e d w ith r a d i a t i n g c r e n e l l a e .

m a in ly s im p le w i t h some i m p l a n t e d .

e l l a e p r e s e n t on o p p o s i t e s i d e o f d i s c .
d ia m e ter, su rro u n d e d by a t u b e - l i k e r i d g e .

B ifu rc a tin g cren ­

Lumen c i r c u l a r , 1 mm*
No c e n t r a l a r e a .

R em arks:

A bundant i n t h e B e l l an d F© rro n P o i n t i n P r e s q u e I s l e

co u n ty .

A ls o o c c u r s i n t h e Nowway P o i n t an d t h e P a r t r i d g e P o i n t

fo rm a tio n s.

Type sp e c im e n fro m t h e B e l l s h a l e , R o c k p o r t Q u a r r y .

15
C ■ C • 1 - D
P la te 1
C irc u la r cro ss s e c tio n .

D a v ie s

F ig u re 4
D ia m e te r 2 t o 7 mm.

C o lu m n als

s i m i l a r , 0 . 7 mm. t h i c k and s l i g h t l y k e e l e d on p e r i p h e r y .
A r t i c u l a t e s u r f a c e g r i l l e d w i t h s im p le and a few b i f u r c a t i n g
c re n e lla e .

A r tic u la te su rfa ce s l i g h t l y concave.

Lumen c i r c u l a r ,

0*1 mm. w id e , s u r r o u n d e d b y a t u b e - l i k e r i d g e , 0 . 2 mm* w id e .
R em ark s:

Common i n t h e B e l l s h a l e a t R o c k p o r t and R o g e rs C i t y .

C - C - I - E D a v ie s
P la te I
C irc u la r cro ss s e c tio n .

F ig u re 5
D ia m e te r 4 mm.

A n n u la te:

D isc

1 mm. t h i c k , s l i g h t l y k e e l e d a l t e r n a t i n g w i t h d i s c 0 . 1 mm.
th ic k .

A r tic u la te su rfa ce s l i g h t l y concave.

s im p le c r e n e l l a e .

G r ill e d w ith

Lumen c i r c u l a r , 0 . 5 mm. w i d e , s u r r o u n d e d

b y a t u b e - l i k e r i d g e w h ic h i s g r i l l e d on t h e a r t i c u l a t e s u r f a c e .
R em ark s:

R e s e m b le s o t h e r s i n S e c t i o n C - C - 1 b u t t h e a r t i c u l a t e

s u r f a c e i s l e s s c o n c a v e an d t h e t u b e s u r r o u n d i n g t h e lumen i s
n o t so p r o m i n e n t .

O c c u rs i n t h e Norway P o i n t f o r m a t i o n a t Seven

M ile Dam, A lp e n a C o u n ty .

C - C - 1 - F
P la te I
C irc u la r cro ss s e c tio n .

F ig u re 6
D ia m e te r 6 t o 9 mm.

A l l d i s c s s i m i l a r , 1 . 2 mm. t h i c k *
a n d s m o o th .

D a v ie s

A n n u la te:

P e r i p h e r y s l i g h t l y con vex

Some d i s c s s l i g h t l y k e e l e d a l o n g t h e p e r i p h e r y .

16
E v e r y f o u r t h d i s c o c ca .s io ri8 .lly n o d o se*
l y c o n ca v e *

A rtic u la te su rface s lig h t-

G r i l l e d w i t h s im p le c r e n e l l a e *

mm. d i a m e t e r .

Lumen c i r c u l a r , 0 .2

S u r r o u n d e d b y a t u b e - l i k e r i d g e 0 . 2 mm. w i d e .

No

c e n tra l area.
R e m a rk s :

O c c u rs i n t h e B e l l s h a l e a t t h e R o c k p o r t Q u a r r y .

S e c t i o n C - C - 2 D a v ie s
C v clo cv clo p ae
a n d no c e n t r a l a r e a .

w i t h a f l a t a r t i c u l a t e s u r f a c e , s m a l l lum en,
S e c t i o n t y p e C ^ C - 2 — A.

a s l i g h t l y c o n cav e a r t i c u l a t e

su rface.

C - C - 2 - A
P la te I
C irc u la r cro ss s e c tio n .
s im ila r.
th ic k .

D a v ie s

F ig u re 8
D ia m e te r 4 t o 8 mm.

P e r i p h e r y p l a n e an d sm o o th .
A rtic u la te su rface f l a t ;

R em ark s:

C o lu m n als

E a c h d i s c a b o u t 1 mm.

g r i l l e d , c r e n e l l a e m ain ly

b i f u r c a t i n g w i t h many s h o r t , i m p l a n t e d .
a b o u t 1 mm. i n d i a m e t e r .

One fo rm shows

Lumen c i r c u l a r ,

No c e n t r a l a r e a .

V ery common i n t h e Genshaw f o r m a t i o n a n d c o n f i n e d t o i t .

Type s p e c im e n fr o m R o b e r t s S c h o o l c o r n e r , P r e s q u e I s l e c o u n t y .
C - C - 2 - B
P la te I
C irc u la r cross s e c tio n .
P e r i p h e r y p l a n e a n d s m o o th .
su rface f l a t ,
th e p e rip h e ry .

D a v ie s

F ig u re 9
D ia m e te r 5 mm.

D iscs s i m i l a r .

T h i c k n e s s a b o u t 1 . 5 mm.

A rtic u la te

g r i l l e d w i t h c o a r s e c r e n e l l a e w h ic h b i f u r c a t e a t
No c e n t r a l a r e a .

Lumen c i r c u l a r , 1 mm. i n d iam -

17
e te r*

A bout h a l f way f r o m t h e c e n t e r t o t h e p e r i p h e r y t h e

c r e n e l l a e a r e c ro s s e d by a l i n e c o n c e n tr ic a b o u t th e c e n te r*
R em ark s:

F ou nd i n t h e M arv in b e d s i n t h e A f to n a r e a *

Very

common i n t h e G r a v e l P o i n t a n d P e t o s k e y f o r m a t i o n s i n t h e w e s t e r n
p a r t of th e S ta te *

C - C - 2 - C
P la te I
C irc u la r cross s e c tio n .

D a v ie s

F i g u r e 7*
D ia m e te r 5 mm*

P e r i p h e r y s t r o n g l y c o n v ex and smooth*

D is c s s i m i l a r .

A rtic u la te su rface

f l a t to s l i g h t l y con cav e, g r i l l e d w ith f i n e r a d i a t i n g c r e n e l l a e .
Lumen c i r c u l a r , a b o u t 1 mm. i n d i a m e t e r .
R e m a rk s :
P o in t.

Common i n t h e

P a rtr id g e P o in t

No c e n t r a l a r e a .
fo rm a tio n a t P a r tr id g e

A ls o common i n t h e Dock S t r e e t c l a y .

C - C - 2 - D
P la te I
C irc u la r cro ss s e c tio n .

D a v ie s

F i g u r e 28
D ia m e te r 5 mm*

C o lu m n a ls a l t e r n a t e :

P r o t r u d i n g c o lu m n a l w i t h a c o n v ex p e r i p h e r y a l t e r n a t i n g w i t h a n o n p r o t r u d i n g one w i t h a p l a n e p e r i p h e r y .

C o lum n als a b o u t 1 . 4 mm. t h i c k .

A r t i c u l a t e s u r fa c e f l a t , c r e n e l l a e s im p le .

No c e n t r a l a r e a .

Lumen c i r c u l a r , 1 . 2 mm. i n d i a m e t e r .
R em ark s:

Common i n t h e Genshaw,

s o u t h o f B la c k L a k e ,

S. E .c o r n e r s e c t i o n 25 ,

C heboygan c o u n t y .

3 m ile s

18
C - C - 2 - £
P la te I
C irc u la r cross s e c tio n .
s i m i l a r , a b o u t 1 . 5 ram. t h i c k .
A rtic u la te su rface f l a t .
im p la n te d .

D a v ie s

F i g u r e 14
D ia m e te r 3 t o 4 mm.

C olu m nals

P e r i p h e r y p l a n e an d sm o o th.

C r e n e l l a e m a in ly b i f u r c a t i n g , some

Lumen c i r c u l a r , e x t r e m e l y s m a l l , 0 .0 5 mm. d ia m e te r *

No c e n t r a l a r e a .
R em ark s:

O c c u rs i n t h e Dock S t r e e t c l a y ,

T h u n d e r Bay Q u a r r y ,

A lp e n a .

C - C • 2 ■ F
P la .te I
C irc u la r cro ss s e c tio n .

D a v ie s

F i g u r e 13
D ia m e te r 5 mm. A n n u l a t e ,

C o lum n als

arranged in s e r ie s of fo u r:
1.

T h i c k d i s c , 1 mm. t h i c k ;

a b o u t 0 . 3 ram. w id e r t h a n d i s c s

2 an d 4 .
2.

T h i n d i s c , 0 . 2 mm. t h i c k .

3.

T h i c k d i s c , 0 . 5 mm. t n i c k ;

a b o u t 0 . 1 ram. wide* t h a n d i s c s

2 and 4 .

4.

T h i n d i s c , 0 . 2 mm. t h i c k .

A r tic u la te su rfa c e s l i g h t l y concave.
im p la n te d c r e n e l l a e .
R e m a rk s :
P o in t.

G r i l l e d w i t h s im p le and

Lumen c i r c u l a r , 1 ram. i n d i a m e t e r .

O c c u rs i n t h e P a r t r i d g e P o i n t f o r m a t i o n a t P a r t r i d g e

19
C * C - 2 - G
P la te I I

D avi e s

F ig u re 4

C irc u la r cro ss s e c tio n .

D ia m e te r 2 t o 3 mm.

A n n u la te,

C o lu m n a ls i n s e r i e s o f t h r e e s
1.

D isc 3 mm. d i a m e t e r , p e r i p h e r y co n v ex and sm o o th .

2.

D is c 2 . 5 mm. d i a m e t e r ; p e r i p h e r y p l a n e a n d sm o o th .

3.

D is c 2 . 5 mm. d i a m e t e r ; p e r i p h e r y p la n e a n d sm o o th .

D i s c s a b o u t 0 . 5 mm. t h i c k .

A rtic u la te surface f l a t ; g r i l l e d

w ith s im p le , f i n e c r e n e l l a e .
R e m a rk s :

Lumen c i r c u l a r , 0 . 2 mm. d i a m e t e r .

O c c u rs i n t h e F e r r o n P o i n t f o r m a t i o n a t B la c k L a k e .

S e c tio n 0 -

C - 3

C y clo cy clo p ae w ith a

f la t a rtic u la te

an d a n a rro w c e n t r a l a r e a .

P la te I

D ia m e te r 4 t o 7 mm.

D i s c s s i m i l a r , a b o u t 1 mm. t h i c k .

A bundant i n t h e

A n n u late:

P e r i p h e r y p l a n e and sm o o th .

C r e n e l l a e m a in ly s im p le w i t h some

Lumen c i r c u l a r , 0 .7 5 mm. d i a m e t e r .

a b o u t 0 . 5 t o 0 . 8 mm. m ade.
R e m a rk s:

D a v ie s

F i g u r e 10

C irc u la r cross s e c tio n .

im p la n te d .

s u r f a c e , s m a l l lum en,

S e c t i o n t y p e C - C - 3 - A.

C - C - 3 - A

A rtic u la te su rface f l a t .

D a v ie s

C en tral area

Smooth and f l a t .
Genshaw,

S. E-

c o rn e rs e c tio n 25,

3 m i l e s s o u t h o f B la c k L a k e , Cheboygan c o u n ty and a t o t h e r p l a c e s
i n C heboygan and P r e s q u e I s l e c o u n t i e s .

A lso o c c u r s i n t h e Dock

2D
S t r e e t c l a y , t h e Norway P o i n t f o r m a t i o n an d t h e Beebe b e d s .

C -

C- 3 - B

P la te I

F ig u re 11.

C irc u la r cro ss s e c tio n .
P e r i p h e r y p l a n e and s m o o th .
u la te su rface f l a t .
R em ark s:

D avi e s

D ia m e te r 2 mm.

A ll d is c s s im ila r .

C r e n e l l a e c o a r s e and s i m p l e .

A rtic ­

Lumen c i r c u l a r , 0 . 2 mm* d i a m e t e r .

O c c u rs i n t h e Genshaw, S . E . c o r n e r s e c t i o n 2 5 , 3 m i l e s

s o u t h o f B la c k L a k e , C heboygan C o u n ty .

A lso o c c u r s i n t h e Dock

S t r e e t c l a y and t h e G r a v e l P o i n t f o r m a t i o n .

S e c tio n C - C - 4
C y clo cy clo p ae w ith
and la r g e c e n t r a l a r e a .

a f la t a rtic u la te

P la te I
C irc u la r cro ss s e c tio n .

o n ly .

s u r f a c e , s m a l l lu m en ,

S e c t i o n t y p e C - C - 4 - A.

C - C - 4 - A

1 mm. t h i c k .

D a v ie s

Da v i e s

F i g u r e 12
D ia m e te r 2 t o 4 mm.

A rtic u la te su rface f l a t .

G r i l l e d alo n g p e rip h e ry

C r e n e l l a e c o a r s e , a b o u t 0 .3 mm. l o n g .

and s m o o th , a b o u t 0 . 5 mm. w i d e .

D iscs s i m i l a r ,

C en tral area f l a t

Lumen c i r c u l a r , 0 . 2 mm. i n d i a ­

m e te r.
R e m a rk s :

A bu nd ant i n t h e Genshaw a t t h e S . E . c o r n e r s e c t i o n 2 5 ,

3 m i l e s s o u t h o f B la c k L a k e , Cheboygan c o u n ty a n d a t o t h e r p l a c e s
i n C heboygan and P r e s q u e I s l e c o u n t i e s .
G rav el P o in t fo rm a tio n .

A lso o c c u r s i n t h e

21
C - G - 4 - B
P la te I

F i g u r e 19

C irc u la r cross s e c tio n .
n a tes

D ia m e te r 2 t o 5 mm.

1*

D is c 1 mm. t h i c k , k e e l e d .

2.

D is c 0 . 5 mm. t h i c k .

A rtic u la te
lo n g .

D a v ie s

su rface f l a t ;

C en tral area f l a t ,

R e m a rk s :

D is c s a l t e r ­

P e r i p h e r y p l a n e , s m o o th .

c r e n e l l a e a l o n g edge o n l y , a b o u t 1 mm.
sm o o th , a b o u t 0 . 5 mm. w id e .

V ery common i n t h e Genshaw,

S .E . c o rn e r s e c t i o n 25,

3 m i l e s s o u t h o f B la c k Lake and a t o t h e r p l a c e s i n C heboygan
c o u n ty .

O c c u rs a l s o i n t h e F e r r o n P o i n t a n d t h e Norway P o i n t

fo r m a tio n s in P resque I s l e c o u n ty .

C - C —4 —C
P la te I
C irc u la r cro ss s e c tio n .
1 nan. t h i c k .

Da v i e s

F i g u r e 18
D ia m e te r 4 mm.

P e r i p h e r y sm ooth and c o n v e x .

D iscs s i m i l a r .
A rtic u la te surface

f l a t w ith c r e n e lla e a lo n g th e p e rip h e ry o n ly .
0 . 8 mm. l o n g .

C re n e lla e about

Lumen c i r c u l a r , a b o u t 1 . 5 mm. i n d i a m e t e r .

C e n t r a l a r e a sm ooth a n d f l a t , a b o u t 0 . 5 mm. w id e .
R em ark s:

C o n f in e d t o and v e r y common i n t h e Genshaw o f Cheboygan

and P resq u e I s l e c o u n t i e s .
io n 25,

Type s p ec im e n fro m t h e S . E . c o r n e r s e c t ­

3 m i l e s s o u t h o f B la c k L a k e ,

C heboygan c o u n t y .

22
C - C - 4 P la te X

D

D a v ie s

F i g u r e 15

C irc u la r cross s e c tio n .

D ia m e te r 5 mm.

A n n u la te ,

C oluinnals

in se rie s of fourt
1.

N odose d i s c , 1 mm. t h i c k ;

0 . 2 mm. w i d e r t h a n d i s c s 2 a n d 4 .

2m

N o n -n o d o se d i s c , 0 . 5

mm. t h i c k .

3.

N o n -n o d o se d i s c , 0 . 5

mm. t h i c k ; s l i g h t l y w i d e r t h a n

d iscs

2 and 4 .
4.

N o n-no do se d i s c , 0 .5

mm. t h i c k .

D i s c s 1 an d 3 h av e a c o n v e x , sm ooth p e r i p h e r y .
a p l a n e , sm ooth p e r i p h e r y .

D is c s 2 and 4 have

A rtic u la te su rface f l a t .

c r e n e l l a e a l o n g p e r i p h e r y o n l y , a b o u t 0 . 5 mm. l o n g .
c u l a r , 1 mm. w i d e .
R em ark s:

G rille d ,
Lumen c i r ­

C e n t r a l a r e a f l a t and sm o o th , 1 mm. w id e .

O c c u rs i n t h e B e l l s h a l e a t R o g e rs C i t y .

C - C - 4 - E
P la te I
C irc u la r cro ss s e c tio n .
1 mm. t h i c k .

F i g u r e 16
D ia m e te r 5 mm.

B isc s s i m i l a r ,

P e r i p h e r y s t r o n g l y c o n v e x and s m o o th .

u la te surface f l a t .
0 . 4 mm. l o n g .

Da v i e s

A rtic ­

C re n e lla e a lo n g p e rip h e ry o n ly , about

C e n t r a l a r e a s l i g h t l y d e p r e s s e d , 1 mm. w i d e , sm o o th .

Lumen c i r c u l a r a t c e n t e r o f d i s c .

At a r t i c u l a t e s u r f a c e lumen i s

a f i v e p o i n t e d s t a r , 1 .5 mm. i n w i d t h .

Lumen a b o u t 0 .7 mm. w ide

a t c e n te r of d is c .
R e m a rk s :

C l o s e l y r e s e m b l e s C - C - 4 - C e x c e p t f o r lum en , w h ich

i n C - C - 4 - C i s

c i r c u l a r in a i l p a r t s of th e d isc*

23
O c c u rs i n th© B e l l s h a l e a t R o g e r s C i t y ,
S e c t i o n C * C * 5 D a v ie s
C y c l o c y c l o p a e w i t h a b r o a d lumen an d no c e n t r a l a r e a *

S e c tio n

oype C - C - 5 - A
C - C - 5 - A
P la te I
C ir c u la r c ro s s sec tio n *

D a v ie s

F i g u r e 23
D ia m e te r 7 mm.

A rtic u la te su rface f l a t ,

g r i l l e d w i t h s im p le c r e n e l l a e a l t e r n a t i n g w i t h im p l a n t e d o n e s .
Lumen c i r c u l a r , 2 mm* i n d i a m e t e r .
P e r i p h e r y co n vex and sm o o th .
R em ark s:

D is c a b o u t 1 . 5 mm. t h i c k .

C olum n als s i m i l a r .

O c c u rs i n t h e P a r t r i d g e P o i n t f o r m a t i o n a t P a r t r i d g e

P o in t.
S e c t i o n C - C - 6 D av ies
C y c l o e y e lo p a e

w i t h a b ro a d luraen, s l i g h t l y c o n ca v e a r t i c u l a t e

s u r f a c e and no c e n t r a l a r e a .

S e c tio n ty p e C - C - 6 - A

C - C - 6 * A D a v ie s
P la te I
C irc u la r cross s e c tio n .

F i g u r e 25
D ia m e te r 7 ram.

A n n u la te, a l t e r ­

n a te c o lu m n a ls:
1.

N on -no d ose d i s c , 0 . 5 ram, t h i c k .
sm o o th ;

2.

P e rip h e ry convex,

p r o t r u d e s a b o u t 0 .2 mm.

N o n -n o d o se d i s c , 0 . 2 mm. t h i c k .

P e rip h e ry s l i g h t l y convex.

A r t i c u l a t e s u rfa c e s l i g h t l y concave, g r i l l e d w ith b i f u r c a t i n g

24
c re n e lla e •
R e m a rk s :

Lumen c i r c u l a r , a b o u t 2 mm* i n d ia m e te r *
O c c u rs i n t h e B e l l s h a l e a t R o c k p o rt*

C - C - 6 - B
P la te I

F i g u r e 26

C irc u la r cross s e c tio n .
s i m i l a r , 0*8 mm. t h i c k , k e e le d *
w i t h s im p le c r e n e l l a e .
R e m a rk s :

D a v ie s

D ia m e te r 7 mm. A n n u l a t e , c o lu m n a ls
A rtic u la te surface f l a t , g r il le d

Lumen c i r c u l a r , a b o u t 3 mm. i n d i a m e t e r .

O c c u rs i n t h e B e l l s h a l e a t R o c k p o r t .
C —C — 6 —C
P la te I

C irc u la r cross s e c tio n .

Da v i e s

F i g u r e 24
D ia m e te r 6 mm. A n n u l a t e , C o lum nals

xn s e r i e s of f o u r :
1.

N o n -n o d o se d i s c , 1 mm. t h i c k ;

p e r ip h e ry convex, k e e le d ;

d i s c p r o t r u d e s a b o u t 0 .5 mm.
2.

N o n -n o d o se d i s c , 1 mm. t h i c k ; p e r i p h e r y f l a t and

sm o o th .

3.

N o n -n o d o se d i s c , 1 mm. t h i c k ; p e r i p h e r y c o n v e x , w e a k ly
k e e l e d ; p r o t r u d e s a b o u t 0.25mm.

4.

N o n -n o d o s e , d i s c , 1 mm. t h i c k ; p e r i p h e r y f l a t an d s m o o th .

A r tic u la te s u rfa c e s l i g h t l y concave.

G r i l l e d w i t h s im p le c r e n e l l a e .

Lumen c i r c u l a r , 2 . 5 mm. i n d i a m e t e r .

No

R e m a rk s :

c e n tra l a re a.

O c c u rs i n t h e B e l l s h a l e , R o c k p o r t

Q u a rry and t h e Norway

P o i n t f o r m a t i o n a t Seven M ile Dam, A lp e n a c o u n t y .

25
S e c tio n C - C - 7
C y clo cy c lo p a e

D a v ie s

w i t h a v e r y b r o a d lum en, c o n c a v e a r t i c u l a t e

s u r f a c e an d no c e n t r a l a r e a .

S e c t i o n t y p e C - C - 7 - A.

C - C - 7 - A D a v ie s
P la te I
C irc u la r cro ss s e c tio n .
n a t e t h i c k and t h i n d i s c s .
1 mm. t h i c k .
and f l a t .

F i g u r e 20
D ia m e te r 5 mm.

T h ic k d i s c 1 .5 mm. t h i c k , t h i n d i s c

D iscs e q u a l i n w i d t h .

P e r i p h e r y o f a l l d i s c s sm ooth

A r tic u la te su rfa c e concave;

c re n e lla e .

No c e n t r a . ! a r e a .

A n n u la te; a l t e r ­

g r i l l e d w ith b if u r c a t i n g

Lumen c i r c u l a r , a b o u t 1 .5 ram. i n d i a ­

m e te r.
R e m a rk s:
c o u n ty .

Common i n t h e Genshaw a t R o b e r t s S c h o o l , P r e s q u e I s l e
S i m i l a r fo rm a l s o o c c u r s i n t h e Dock S t r e e t c l a y .
C - C - 7 - B
P la te I

C irc u la r cross s e c tio n .
n a te in s i z e .

Da.v i e s

F i g u r e 27
D ia m e te r 3 t o 6 mm.

1.

N o d o se , 2 mm. t h i c k .

2.

N o n -n o d o s e , 1 .5 mm. t h i c k .

P e r i p h e r y o f d i s c s s l i g h t l y c o n v e x , sm o o th .
s tro n g ly concave.
w id e .

C re n e lla e sim p le .

D iscs a l t e r ­

A rtic u la te su rface

Lumen c i r c u l a r , a b o u t 1 mm.

No c e n t r a l a r e a .

R em ark s:

O c c u rs i n t h e G enshaw,

S .S . c o rn e r s e c tio n 25, 3 m ile s

s o u t h o f B la c k L a k e , C heboygan c o u n t y .

26

S e c tio n C - C - 8

D a v ie s

C y c l o c y c l o p a e w i t h a v e r y b r o a d lu m en , f l a t a r t i c u l a t e
l a c e a n d no c e n t r a l a r e a *

S e c tio n ty p e

C - C - ft - A
P la te I
C irc u la r cross
lla t,

C - C - 8 - A.

D a v ie s

F i g u r e 17

s e c t i o n . D ia m e te r 5 mm*

g r i l l e d w i t h c o a r s e s im p le c r e n e l l a e *

No c e n t r a l a r e a .
R em ark s:

su r-

A rtic u la te su rface
Lumen l a r g e , 1*5 mm.

C o lu m n a ls s i m i l a r , a b o u t 3 mm. t h i c k .

O c c u rs i n t h e Dock S t r e e t c l a y , T h u n d e r Bay Q u a r r y , A lp e n a .

C —C - 8 —B
P la te I
C irc u la r cross
0 . 5 mm. t h i c k ;

D a v ie s

F i g u r e 21

s e c t i o n . D ia m e te r 3 mm.

p e r i p h e r y p l a n e , s m o o th .

^ r e n e lla e s im p le .

No c e n t r a l a r e a .

A l l c o lu m n a ls s i m i l a r .

A rtic u la te su rface f l a t ,

Lumen l a r g e , 1 mm. i n d i a m e t e r .

Lumen c i r c u l a r i n o u t l i n e .
R em ark s:

O c c u rs i n t h e F e r r o n P o i n t s h a l e ,
(j - C - 8 - C
P la te I

C irc u la r cro ss

s e c t i o n . D ia m e te r 4 mm.

R e m a rk s :

A n n u la te:

C olu m n als

One d i s c a b o u t 0 . 1 mm.

P e rip h e ry s l i g h t l y convex.

su rfa c e s lig h tly concave.
2 mm. w i d e .

Da v i e s

F i g u r e 22

a b o u t 0 . 5 mm t h i c k . A l t e r n a t e d i s c s :
w id e r th a n o th e r d i s c .

B la c k Lake Q u a r r y .

C re n e lla e sim p le .

A rtic u la te

Lumen c i r c u l a r ,

No c e n t r a l a r e a .

O c c u rs i n t h e F e r r o n P o i n t f o r m a t i o n , B la c k Lake q u a r r y •

27

S e c tio n C - C - 9
Cy p l o c y c l o p a e
on t h e a r t i c u l a t e

D a v ie s

w i t h a v e r y com plex a r r a n g e m e n t o f c r e n e l l a e
su rface*

S e c tio n ty p e

C - C - 9 - A
P la te I
C irc u la r cro ss s e c tio n .

G - C - 9 - A.

D a v ie s

F i g u r e 29
D ia m e te r 3 mm.

mm. t h i c k , p e r i p h e r y p l a n e and s m o o th .

D iscs s i m i l a r .

1 .5

A rtic u la te surface f l a t .

Lumen v e r y s m a l l , 0 .0 5 mm d i a m e t e r , c i r c u l a r .

No c e n t r a l a r e a .

C r e n e l l a e c o m p le x , c o n s i s t i n g o f f o u r g r o u p s o f s im p le c r e n e l l a e
a l t e r n a t i n g w i t h g r o u p s o f c r e n e l l a e made by one c r e n e l l e
b i f u r c a t i n g i n t o num erous p a r a l l e l c r e n e l l a e .
R em ark s;

O c c u rs i n t h e Dock S t r e e t c l a y ,

S e c t i o n C - C - 10

T h u n d e r Bay Q u a r r y , A lp e n a .

D a v ie s

C y clo cy clo p ae w ith a s ta r - s h a p e d c e n t r a l a r e a .
ty p e

S e c tio n

C - C - 10 - A.
C - C - 10 - A
P la te I
C irc u la r cross s e c tio n .

0 . 3 mm. w i d e .
area s t e l l a t e
R e m a rk s :

D a v ie s

F i g u r e 30
D ia m e t e r 3 mm.

Lumen c i r c u l a r ,

S im p le c r e n e l l a e a l o n g edge o f d i s c o n l y .

C en tral

i n o u t l i n e , sm ooth and f l a t .

O nly one d i s c o f t h i s form was o b s e r v e d .

a w e l l i n E m p ire t o w n s h i p ,
d e p t h o f 1194 t o 1200 f e e t .

I t was fro m

L e e l a n a u c o u n ty ( P e r m i t 5505) a t a
T h i s i s p r o b a b l y ab o v e t h e B e l l s h a l e

a n d i n a s h a l e f a c i e s o f t h e Gensha-w.

The B e l l i s 20 f e e t b e lo w

28

th is

zone*

S e c t i o n C - C - 11

D a v ie s

C y clo cy c lo p a e , a n n u la t e , w ith c y c le s o f e ig h t d is c s to a
se rie s.

S e c t i o n t y p e C - C - 11 - A
C - G - 11 - A
P la te I I

C ir c u la r c ro ss se c tio n *

D a v ie s

F ig u re 1
D ia m e te r 3 mm.

A n n u l a t e , c o lu m n a ls

in s e r ie s of e ig h t d is c s :
1.

N o n -n o d o s e , 0 . 2 mm. t h i c k , p r o t r u d e s 0 . 5 mm.

2.

T h r e e t h i n d i s c s , 0 . 1 mm. t h i c k ; p l a n e ,

3.

T h i n d i s c , 0*1 mm. t h i c k , p r o t r u d e s 0 .2

4.

T h r e e t h i n d i s c s , 0 . 1 mm. t h i c k ; p l a n e ,

smooth p e r i p h e r y .
mm.
sm ooth p e r i p h e r y .

E v e r y f o u r t h d i s c o f 1 ab o v e p r o t r u d e s a b o u t 1 mm..
s u rfa c e g r i l l e d , c r e n e lla e sim p le .
c u la r.

A rtic u la te

Lumen a b o u t 1 mm. w id e , c i r ­

A r tic u la te su rfa ce s l i g h t l y concave.

Remarks*

Common i n i h e B e l l s h a l e a t R o c k p o r t Q u a rry an d R o g e rs C i t y .

C - C - 11 - B
P la te I I
C irc u la r cross s e c tio n .

D a v ie s

F ig u re 2.
D ia m e te r 4 mm.

A n n u la te:

wide

d i s c , 4 mm. i n d i a m e t e r a n d 0 . 8 mm. t h i c k f o l l o w e d by s e v e n s i m i l a r
d i s c s , e a c h 3 mm. i n d i a m e t e r , 0 .5 mm. t h i c k ; p e r i p h e r y p l a n e and
s m o o th .
area.

A rtic u la te su rface f l a t .

C re n e lla e sim p le .

No c e n t r a l

Lumen c i r c u l a r , 1*5 mm. d i a m e t e r .

R e m a rk s:

O c c u rs i n t h e P a r t r i d g e P o i n t f o r m a t i o n a t P a r t r i d g e P o i n t .

29

S e c t i o n G - C ~ 12

D a v ie s

C y c lo cy c l o p a e w i t h a f l a t a r t i c u l a t e s u r f a c e , c o a r s e c r e n e l l a e
u n i t i n g w i t h a b r o a d f l a t r i d g e w hich s u r r o u n d s t h e lumen*

S e c tio n

t y p e C - C - 12 - A

C - C - 12 - A
P la te I I
C irc u la r cross s e c tio n .

D a v ie s

F ig u re 3

D ia m e te r 2 mm.

i l a t and e l e v a t e d a b o v e t h e edge of t h e d i s c *
Lumen c i r c u l a r , 0*25 mra. i n d i a m e t e r .

R e m a rk s :

C o a rse c r e n e l l a e *

Lumen i s s u r r o u n a e d by a

i l a t r i d g e t o w h ic h t h e c r e n e l l a e a r e u n i t e d .
Known fro m o n l y one d i s c .

A rtic u la te su rface

No c e n t r a l a r e a *

P e r i p h e r y p l a n e and sm o o th .

O c cu rs i n t h e Dock S t r e e t c l a y , T h u n d e r Bay Q u a r r y ,

A lp en a.

Group CYCLOFENTAGONOPAE Moore
U y c lo sty li

w i t h c i n q u e f o i l o r p e n t a p e t a l o i d lu m e n s.

S e c tio n C - F - 1

D a v ie s

C y c lo p e n ta g o n o p a e w i t h s m a l l lu m e n s, f l a t a r t i c u l a t e s u r f a c e s ,
an d no c e n t r a l a r e a .

S e c t i o n t y p e C - F - 1 - A.
C - F - 1 - A
P la te I I

C irc u la r cross s e c tio n .

D a v ies

F ig u re 5

D ia m e te r 6 mm.

A n n u l a t e , c o lu m n a ls

in s e r ie s of fo u r:
1.

T h i c k d i s c , 1 .5 mm. t h i c k , s l i g h t l y p r o t r u d i n g , commonly

30

nodose.
3 . . T h i n d i s c , 1 mm. t h i c k ; n o n - p r o t r u d i n g .
3 . M o d e r a t e l y t h i c k d i s c , 1 . 2 mm. t h i c k ;

s lig h tly p ro tru d in g ,

a . T h i n d i s c , 1 mm. t h i c k ; n o n - p r o t r u d i n g .
A rtic u la te surface f la t*

G r i l l e d w i t h c o a r s e , s im p le c r e n e l l a e .

Lumen s l i g h t l y d e p r e s s e d , c i n q u e f o i l i n s h a p e , 1 mm. d i a m e t e r .
R e m a rk s :

O c c u rs i n x h e Dock S t r e e t c l a y an d t h e A lp e n a l i m e s t o n e

a t A lp e n a.

Type s p e c im e n fr o m t h e Dock S t r e e t c l a y ,

T h u n d e r Bay

Q u a r r y , A lp e n a .
C - r - 1 - B
P la te I I
C irc u la r cross s e c tio n .
d isc s:

1.
2.

A rtic u la te

D a v ie s

F ig u re 6 .
D ia m e t e r 6 mm.

T h i n d i s c , 0*5 mm. t h i c k ; k e e l e d , k e e l p r o t r u d e s 0 .5 mm.
T h i n d i s c , 0 . 5 mm. t h i c k ; p e r i p h e r y f l a t ,
su rface f l a t .

sm o o th .

G r i l l e d w i t h f i n e , s im p le c r e n e l l a e .

Lumen 1 . 2 mm. d i a m e t e r , c i n q u e f o i l i n o u t l i n e .
R em ark s:

A n n u la te, a l t e r n a t e

O c c u rs i n t h e Dock S t r e e t c l a y .

No c e n t r a l a r e a .

T h i s fo rm and C - F -

1 - A p r o b a b l y a r e s te m s o f t h e g e n u s M e g i s t o c r i n u s .

C - F - 1 - C
P la te I I
C irc u la r cro ss s e c tio n .

D a v ie s

F ig u re 7
D ia m e te r 6 nun.

e q u a l i n s i z e , a b o u t 1 t o 1 . 2 mm. t h i c k .
A rtic u la te su rface f l a t ,

D is c s a p p r o x i m a t e l y

P e rip h e ry f l a t ,

sm o o th .

g r i l l e d w ith b i f u r c a tin g c r e n e lla e .

Lumen c i n q u e f o i l , 1 mm. i n d i a m e t e r .
R e m a rk s:

O c cu rs i n t h e B e l l s h a l e a t t h e R o c k p o r t Q u a rry and

31
R ogers C ity .

C - F - 1 - D
P la te I I

F ig u re 8

C irc u la r cro ss s e c tio n .
2 mm. t h i c k ;

D a v ie s

D ia m e t e r 5 mm.

p e r i p h e r y f l a t an d sm o o th .

C olu m n als s i m i l a r .

A rtic u la te surface f l a t .

C re n e lla e c o a rse , b if u r c a te a t th e p e rip h e ry .
1

Lumen c i n q u e f o i l ,

mm. i n d i a m e t e r s u r r o u n d e d by a sm ooth a r e a s l i g h t l y d e p r e s s e d .

R em arks :

O c c u rs i n t h e G r a v e l P o i n t f o r m a t i o n , t h e Beebe b e d s ,

an d i n t h e Dock S t r e e t c l a y .

Type s p e c im e n fro m t h e Dock S t r e e t

c l a y , T h u n d e r Bay Q u a r r y , A lp e n a .

T h i s fo rm i s a good in d e x

f o s s i l a s i t o c cu rs r e l a t i v e l y h ig h in th e T ra v e rse in th e e a s te r n ,
c e n t r a l and w e s t e r n p a r t o f t h e S t a t e .
C - F - 1 - E
P la te I I

D a v ie s

F ig u re 9.

C i r c u l a r c r o s s s e c t i o n % D ia m e t e r 5 t o 7 mm.
s i m i l a r , a b o u t 1 ,5 mm. t h i c k .

C o lu m nals

P e r i p h e r y s l i g h t l y co nv ex and

c o v e r e d w i t h f i n e , v e r t i c a l r i d g e s w h ic h a r e p r o l o n g a t i o n s o f
the c r e n e lla e .

A rticu la te surface f l a t ,

Lumen c i n q u e f o i l , 1 mm. w i d e .
R e m a rk s :

crenellae coarse,

sim ple.

No c e n t r a l a r e a .

Common i n t h e Genshaw, S .E . c o r n e r s e c t i o n 2 5 , 3 m i l e s

s o u t h of B la c k L a k e , Cheboygan c o u n t y .

A s i m i l a r fo rm o c c u r s i n

t h e F e r r o n P o i n t s h a l e i n C heboygan c o u n ty b u t d i f f e r s i n a some­
w hat a n n u la te c h a r a c te r .

32
S e c t i o n C * F - 2 D a v ie s
C y c l o p e n t a g onopae w i t h a s m e l l lu m e n , f l a t t o s l i g h t l y concave a r t i c u l a t e
ty p e

s u r f a c e , an d a n a rro w c e n t r a l a r e a #

S e c tio n

C - F - 2 - A.

C * F - 2 - A

D a v ie s

P l a t e I I F i g u r e 10
C i r c u l a r c r o s s s e c t i o n , D ia m e te r 5 t o 7 mm.
2 . 5 ram# an d 1 mm. t h i c k *
su rfa c e s l i g h t l y concave.
C re n e lla e sim p le .
R e m a r ts s

A lte rn a te d is c s ;

P e rip h e ry s l i g h t l y convex.
C e n tral are a f l a t ,

A rtic u la te

sm o o th , 1 mm# wide#

Lumen c i n q u e f o i l , 1 .0 t o 1 . 5 mm. i n d i a m e t e r .
0

O c c u rs i n t h e F e r r o n % in t s h a l e , B la c k Lake Q u a r r y .
C - F - 2 - B
P la te I I I

C irc u la r cro ss s e c tio n .
E a c h a b o u t 2 mm. t h i c k .
surface f l a t .

D a v ie s

F ig u re I
D ia m e te r 3 mm.

D is c s s i m i l a r .

P e rip h e ry b ro a d ly c o n v e x .-

G r i l l e d v /ith s i m p l e » c o a r s e c r e n e l l a e .

c i n q u e f o i l , 0 . 2 mm. w i d e .

A rtic u la te
Lumen

C e n t r a l a r e a sm ooth and f l a t , 0 . 2 ram.

w id e •
R em ark s:
of A fto n .

O c c u rs i n t h e B eeb e b e d s ,

Beebe S c h o o l , 2 l / 2 m i l e s s o u th

33
S e c tio n

C - F - 3

D a v ie s

G y c l o p e n t a g onopa.e w i t h no c e n t r a l a r e a * l a r g e lumen and a
v e r y w id e c r o s s s e c t i o n .

S e c tio n ty p e

0 - F - 3 - A.

Lumen

in d is tin c tly c in q u e fo il.
C - F - 3 - A
P l a t e XI
C irc u la r cross s e c tio n .
s im ila r.

F i g u r e 11
D ia m e te r 8 mm.

A bout 1 mm. t h i c k , s t r o n g l y k e e l e a .

g r i l l e d w ith f i n e ,
3 mm. w i d e .
B.emarks:

D a v ie s

o ifu rc a tin g c re n e lla e .

A rtic u la te su rface f l a t .

A n n u la te, d is c s
A rtic u la te su rface

Lumen c i n q u e f o i l , a b o u t

No c e n t r a ^ a r e a .

O c c u rs i n t h e Dock S t r e e t c l a y , T h u n d e r Bay Q u a rry ,

A l p e n a , a n d i n t h e M arv in b e d s a t A f t o n .
C - F - 3 * B

D a v ie s

P l a t e I I F i g u r e 12
C irc u la r cross s e c tio n .

D ia m e te r 13 mm.

v e r y t h i n , a b o u t 0 . 5 mm* t h i c k .
m e n t.

P la te s are ir r e g u la r in arran g e­

E a c h a l t e r n a t e p l a t e h a s a t e n d e n c y t o be s l i g h t l y t h i c k ­

e n e d and p r o t r u d e s s l i g h t l y .
fin e b ifu rc a tin g c re n e lla e .
w id e .

Bach p l a t e i s

A rtic u la te

Lumen i s c i n q u e f o i l , a b o u t 3 mm.

A rtic u la te su rface is f l a t .

R e m a rk s 5

s u rfa c e g r i l l e d w ith

No c e n t r a l a r e a .

O c c u rs i n t h e P a r t r i d g e P o i n t a t P a r t r i d g e P o i n t , and

i n t h e Norway P o i n t a t F o u r M ile Dam, A lp en a c o u n t y .
Section C - F - 4
Cvclopentagonopae
face,

D a v ies

w i t h a l a r g e rumen, f l a t a r t i c u l a t e

and no c e n t r a l a r e a .

S e c t i o n uype C - F - 4 - A.

sur­

34
C - F - 4 - A
P la te I I
C irc u la r cross s e c tio n .
1 mm. t h i c k .
fla t.

D a v ie s

F i g u r e 13
D ia m e te r 5 mm.

P e r i p h e r y co n v ex and sm o o th .

D is c s s i m i l a r .
A rtic u la te su rface

C r e n e l l a e c o a r s e , m a i n l y s i m p l e , some i m p l a n t e d .

c e n tra l area.
R e m a rk s :

No

Lumen c i n q u e f o i l , 1 .8 mm. i n d i a m e t e r .

O c c u rs i n t h e Genshaw i n Cheboygan c o u n t y .
S e c tio n C - F - 5

Cy c l o p e n t a g o n o p a e
c u la te su rfa ce s.

D a v ie s

w i t h l a r g e c e n t r a l a r e a s and f l a t a r t i ­

S e c tio n ty p e

C - F - 5 - A.

C - F - 5 - A D a v ie s
P la te I I
C irc u la r cross s e c tio n .
2 mm t h i c k .

F i g u r e 14
D ia m e te r 4 mm.

C o lum nals s i m i l a r ,

P e r i p h e r y p l a n e and s m o o th , c o v e r e d w i t h c o a r s e

v e r t i c a l r i d g s w h ic h a r e p r o l o n g a t i o n s of t h e c r e n e l l a e .
c i n q u e f o i l , 1 mm. i n d i a m e t e r .

Lumen

A r t i c u l a t e s u r f a c e f l a t v /ith

c o a r s e , s im p le c r e n e l l a e a b o u t 1 .5 mm. lo n g a l o n g t h e p e r i p h e r y .
C en tra l area f l a t ,
R e m a rk s:

s m o o th , 0 . 5 mm. w i d e .

O c c u rs i n t h e F e r r o n P o i n t a t B la c k Lake Q u a rry and i n

t h e G enshaw ,

S . E . c o r n e r s e c t i o n 2 5 , 3 m i l e s s o u t h o f B la c k L a k e ,

C hebo yg an c o u n t y .
C - F - 5 - B
P la te I I
C irc u la r cro ss s e c tio n .

D a v ie s

F i g u r e 15

D ia m e te r 3 t o 5 mm.

C o lum n als

35

sim ila r.
k e e le d .

E a c h d i s c a b o u t 1 mm* " th ic k .
A rtic u la te

ip h e ry o n ly .

S im p le c r e n e l l a e a l o n g "the p e r ­

C r e n e l l a e a b o u t 0 .7 5 mm. l o n g .

s m o o th , 1 mm. w i d e .
R e m a rk s:

su rface f l a t .

P e r i p h e r y convex and

C en tral area f l a t ,

Lumen c i n q u e f o i l , a b o u t 0*5 mm. d i a m e t e r .

O c c u rs i n t h e Genshaw,

S .E . c o r n e r s e c t i o n 2 5 , 3 m i l e s

s o u t h o f B la c k L a k e , C heboygan c o u n t y .
C - F - 5 ■ C
P la te I I
C irc u la r cross s e c tio n .
fla t,
lo n g .

D avie s

F i g u r e 16
D ia m e te r 4 mm.

g r i l l e d a lo n g th e p e rip h e ry o n ly .

A rtic u la te su rface

C r e n e l l a e c o a r s e , 0 . 2 mm.

C e n t r a l a r e a a b o u t 1 mm. w i d e , f l a t and sm o o th .

c i n q u e f o i l , 1 . 5 mm. w i d e .

Lumen

S l i g h t s w e l l i n g a t edge o f lum en.

D i s c s a b o u t 0 . 7 5 mm. t h i c k .

P e r i p h e r y s l i g h t l y c o n v e x , s m o o th .

A rra n g e m e n t o f c o lu m n a ls unknown a s o n l y s i n g l e d i s c s o f t h i s
f o r m h a v e so f a r b e e n f o u n d .
R em ark s:

O c c u rs i n t h e Dock S t r e e t c l a y ,

A lp e n a and i n t h e G r a v e l P o i n t f o r m a t i o n .

T h u n d e r Bay Q u a r r y ,
T h i s io r m i s p r o b a b l y

a good i n d e x f o s s i l f o r t h i s p a r t o f t h e u p p e r T r a v e r s e .

C - F - 5 - D
P la te I I
C irc u la r

cross s e c tio n .

P e rip h e ry s l i g h t l y convex.

F i g u r e 17

D ia m e t e r 4 mm.

E ach a l t e r n a t e

d ia m e te r s l i g h t l y le s s th a n o th e r. ,
c u la te surface f l a t .

D a v ie s

C olum nals a l t e r n a t e .
d isc occurs w ith a

D i s c s O.S mm. t h i c k .

C r e n e l l a e a l o n g edge o f d i s c , s im p le *

A rti­
Lumen

36

c i n q u e f o i l , 1 mm. i n d i a m e t e r .

C e n t r a l a r e a 0 .5 mm, w id e ,

s l i g h t l y s w e l l e d and s m o o th .
I

R e m a rk s :

O c c u rs i n t h e lo w e r A lp e n a L im e s to n e ,

M ic h ig a n A l k a l i

Q u a rry ,A lp e n a .

C - F - 5 * E
P la te I I I
C irc u la r c :o ss s e c tio n .

D a v ie s

F ig u re 4
D ia m e te r 5 mm.

A n n u la te,

C o lu m n a ls

xn s e r i e s o f f o u r :
1.

D is c 1 mm. t h i c k , p e r i p h e r y s t r o n g l y c o n v e x , p r o t r u d e s 1 mm.

2.

D is c 0 . 2 mm. t h i c k , p e r i p h e r y f l a t and sm o o th .
D is c 0 . 4 mm. t h i c k ,

ft.

p e r i p h e r y c o n v e x , p r o t r u d e s 0 . 2 mm.

D is c 0 . 2 mm. t h i c k , p e r i p h e r y f l a t ,

A rtic u la te surface f l a t .
C re n e lla e sim p le .

sm o o th .

G r i l l e d a lo n g th e p e rip h e ry o n ly .

C e n t r a l a r e a smooth an d f l a t .

Lumen c i n q u e -

x o i l , 1 mm. w i d e .
R em ark s:

O c c u rs i n t h e Dock S t r e e t c l a y ,

C - F - 5 - F
P la te I I I
C irc u la r cro ss s e c tio n .
for i l l e d a l o n g t h e p e r i p h e r y .

T h u n d e r Bay Q u a r r y , A lp e n a .

D a v ie s

F ig u re 6

D ia m e te r 3 ram.

C r e n e l l a e l i n e , 0 .2 5 mm. l o n g .

c i n q u e f o i l i n o u t l i n e , 0 . 5 mm. i n d i a m e t e r .
ed by a

low r i d g e .

Lumen

The lumen i s s u r r o u n d ­

C e n t r a l a r e a a b o u t 1 mm. w id e , sm o o th , d e p r e s s ­

ed b e lo w t h e p e r i p h e r y and r i d g e *
ip h e ry convex.

A rtic u la te surface

D isc a b o u t 0 .5 mm. t h i c k .

A rra n g e m e n t o f d i s c s unknown.

P er­

37
R em arks*

R e s e m b le s C - F - 5 - C e x c e p t t h a t c e n t r a l a r e a i n

C - F - 5 - C i s

nox d e p r e s s e d .

O ccure m t h e Dock S t r e e t c l a y ,

T h u n d e r Bay Q u a r r y , A lp e n a .
S e c tio n G - F - 6

D a v ie s

C y c l o p e n ta g o n o p a e w i t h m o d e r a t e l y w ide c o l u m n a l s , v e r y b r o a d ,
d i s t i n c t l y c i n q u e f o i l lum ens and no c e n t r a l a r e a .
ty p e

S e c tio n

C - F - 6 - A.

C - F - 6 - A
P la te I I
C irc u la r cross s e c tio n .

D a v ie s

F i g u r e 18
D ia m e te r 5 t o 7 mm.

A n n u la te,

a l t e r n a t e p r o t r u d i n g and n o n - p r o t r u d i n g d i s c s , 7 and 6 mm. w ide
re sp e c tiv e ly .

1 .5 mm. t h i c k .

P e rip h e ry convex.

A rtic u la te

s u r f a c e f l a t , g r i l l e d ; c r e n e l l a e c o a r s e and b i f u r c a t i n g .

Lumen

c i n q u e f o i l , l a r g e , 3 mm. i n d i a m e t e r .
R e m a rk s:

O c c u rs i n t h e Dock S t r e e t c l a y , T h u n d e r Bay Q u a r r y ,

A lp e n a ; a n d i n t h e F e r r o n P o i n t s h a l e , B la c k Lake Q u a rry .
C - F - 6 - B
P la te I I
C irc u la r

cross s e c tio n .

D a v ie s

F i g u r e 19
D ia m e te r 5 t o 7 mm.

A lte rn a te

d isc s.

D i s c s 1 mm. t h i c x a l t e r n a t i n g wixh a g ro u p e a c h 0 . 2 ram.

th ic k .

T h i c k d i s c s co n v ex on p e r i p n e x y an a p r o t r u d e s l i g h t l y .

A rtic u la te surface f l a t , g r il le d .
Some i m p l a n t e d c r e n e l l a e .

C re n e lla e c o a rse , b if u r c a tin g .

Lumen c i n q u e f o i l , 3 mm. i n d i a m e t e r .

No c e n t r a l a r e a .
R em arks:

O c c u rs i n t h e Dock S t r e e t c l a y ,

T h u n d e r Bay Q u a r r y , A lp e n a .

38

C - F - 6 - C
P la te I I
C ir c u la r c ro s s sec tio n *

F i g u r e 20
D ia m e te r 7 mm*

1.

T h i c k d i s c , 1 mm. t h i c k ;

2.

T h i n d i s c * 0 . 2 mm*

A r tic u la te su rface f l a t ,
c in q u e fo il,
R e m a rk s:

D avi e s

A l t e r n a t e c o lu m n a ls ;

p e r i p h e r y smooth an d c o n v e x .

th ic k ;

p e r i p h e r y smooth and c o n v e x .

c re n e lla e co arse, b ifu r c a tin g .

Lumen

3 mm. i n d i a m e t e r .

O c c u rs i n t h e Beebe b e d s ,

Beebe s c h o o l , 2 l / 2 m i l e s

s o u t h o f A f t o n , an d t h e F e r r o n P o i n t s h a l e a t B la c k Lake Q u a r r y .
C - F - 6 - D

D a v ie s

P la te I I I F ig u re 2.
C irc u la r cro ss s e c tio n .

D ia m e te r 7 mm.

0 . 5 mm. t h i c k , p r o t r u d e 0 . 2 mm.

D iscs s i m i l a r ,

A rtic u la te su rface f l a t , g r i l le d .

C r e n e l l a e m a i n l y b i f u r c a t i n g , some i m p l a n t e d .

No c e n t r a l a r e a .

Lumen c i n q u e f o i l , 4 mm. d i a m e t e r .
R em ark s:

O c c u rs i n t h e B e l l s h a l e ,
C - F - 6 - E
P la te I I I

C irc u la r cross s e c tio n .

R ockport Q uarry.
D a v ie s

F ig u re 3
D ia m e t e r 4 mm.

D iscs a l t e r n a t e .

One d i s c p r o t r u d e s w i t h co n v ex p e r i p h e r y , o t h e r d i s c p la n e p e r ­
ip h ery .

D i s c s a b o u t 1 ram. t h i c k .

sim p le .

Lumen c i n q u e f o i l , 1 .2 mm. w id e .

R e m a rk s :

A rtic u la te su rface f l a t , c re n e lla e
No c e n t r a l a r e a .

O c c u rs i n t h e Norway P o i n t f o r m a t i o n ,

A lp e n a c o u n t y .

F o u r M ile Dam,

39

C - F - 6 - F
P la te I I I

Davi e s

F ig u re 5

C irc u la r c ro ss sec tio n *

D ia m e te r 5 t o 9 mm*

A rtic u la te

s u r f a c e s l i g h t l y c o n c a v e , c r e n e l l a e s im p le w i t h numerous i m p l a n e t d
o n e s*

A r t i c u l a t e s u r f a c e s l o p e s to w a r d s lum en.

Lumen l a r g e , 4 mm.

i n d i a m e t e r , c i n q u e f o i l i n s h a p e ; p e r i p h e r y sm o o th , c o n v e x .

A rrange­

m e n ts o f c o lu m n a ls unknown*
R e m a rk s :

O c c u rs i n t h e F e r r o n P o i n t s h a l e ,

G roup

CYCLOSTELLANOPAE D a v ies

C y c l o s ty li w ith a s t e l l a t e

S e c tio n

( f i v e sid e d s t a r )

C - T - 1

S e c tio n ty p e

P la te I I I

0 . 8 mm. t h i c k ;
s im ila r.

s u r f a c e and a l a r g e

C - T - 1 - A*

C - T - 1 - A

C irc u la r cross s e c tio n .

D a v ie s

F ig u re 7 .
D ia m e te r 7 mm.

C o lum n als a b o u t

p e rip h e ry convex, s tro n g ly k e e le d .

A rtic u la te su rface f l a t ,

edge o f d i s c o n l y .

lum en.

D a v ie s

C y c lo ste lla n o p a e w ith a f l a t a r t i c u l a t e
c e n tra l area.

B la c k Lake Q u a r r y .

D is c s

c r e n e l l a e sim p le ; alo n g

C e n t r a l a r e a f l a t , a b o u t 1 mm. w id e .

Lumen

s t e l l a t e , 0 . 8 mm. d i a m e t e r ; s u r r o u n d e d by a c e n t r a l d e p r e s s i o n
0 .2

mm. w i d e .

R em ark s:

O c c u rs m t h e Genshaw f o r m a t i o n , S .E . c o r n e r s e c t i o n 2 5 ,

40

3 m i l e s s o u t h o f B la c k L a k e ,

G roup

Cheboygan c o u n t y .

CYCLOPENTANQPAS D a v ie s

Cy c l o s t y l i w i t h a p e n t a g o n a l lu m e n .

S e c tio n

C- P

- 1

D a v ie s

C y c l o p e n ta n o p a e w i t h a f l a t a r t i c u l a t e
area.

S e c tio n ty p e C -

P- 1

C - P

- A.

- 1 - A

P la te I I I
C ross s e c t i o n c i r c u l a r .
su rface f l a t ,

D a v ie s

F ig u re 8

D ia m e te r 3 t o 5 mm.

A rtic u la te

g r i l l e d w i t h s im p le an d b i f u r c a t i n g c r e n e l l a e .

Lumen p e n t a g o n a l i n o u t l i n e .
0 . 8 mm. t h i c k .
P.emarks:

s u r f a c e and no c e n t r a l

1 mm. i n d i a m e t e r .

P e rip h e ry convex.

A rra n g e m en t o f d i s c s unknown.

O c cu rs i n t h e B e l l s h a l e ,

L e e lan a u c o u n ty .

(P e rm it 5505).

D is c s a b o u t

W e ll i n E m pire to w n s h i p ,

1285 t o 1290 f e e t .

G roup CYCLOLINEANOPAE D a v ie s
C y c lo s ty li w ith s t r a i g h t , s l i t - l i k e

S e c tio n C - S - 1

lu m e n s .

D a v ies

Cy c l o l i n e a n o p a e w i t h a f l a t a r t i c a u l a t e s u r f a c e an d a c e n t r a l
area.

S e c tio n ty p e

C - g - 1 - A.

41

C - 3 - 1 -A
P la te I I I
C irc u la r cro ss s e c tio n .
sim m lar.

D a v ie s

F ig u re 9
D ia m e te r 2 t o 4 mm.

P e r i p h e r y p l a n e an d s m o o th .

A l l c o lu m n a ls

C olu m nals a b o u t 1 mm. t h i c k .

A r t i c u l a t e s u rfa c e f l a t , g r i l l e d alo n g p e rip h e ry o n ly .
c o a r s e , s i m p l e , a b o u t 0 . 2 mm. l o n g .
l o n g , 0 . 1 mm. w i d e .
R e m a rk s :

C re n e lla e

Lumen a n a rro w s l i t 0 .7 5 mm.

C en tral area f l a t ,

sm o oth , 1 ram. w id e .

Common i n t h e B e l l s h a l e a t t h e E m pire to w n s h i p , L e e la n a u

c o u n t y w e l l and i n t h e Dock S t r e e t c l a y , T h u n d e r Bay Q u a r r y , A lp e n a .

C - S - 1 - B
P la te I I I
C irc u la r cro ss s e c tio n .
sim ila r.

D a v ie s

F i g u r e 10
D ia m e te r 2 t o 3 mm.

P e r i p h e r y s l i g h t l y c o n c a v e , sm o o th .

1 , 5 mm. t h i c k .

A rtic u la te surface f l a t .

0 . 0 1 mm. w i d e .

C olum n als a b o u t

G r i l l e d a l o n g edge o f

d i s c o n l y ; s im p le c r e n e l l a e , 0*2 mm. l o n g .
0 . 7 mm. l o n g ,

A l l c o lu m n a ls

Lumen a n a rro w s l i t

C e n t r a l a r e a f l a t t o s l i g h t l y d ep ­

r e s s e d , s m o o th , 1 mm. w i d e .
R em arks:

D i f f e r s fro m C - S - l - A i n

t h a t t h e p e r i p h e r y on

t h a t fo rm i s p l a n e w h i l e on C - S - 1 - B i t i s c o n c a v e .

O ccu rs

m t h e E m p ire t o w n s h i p w e l l , L e e la n a u c o u n ty i n t h e B e l l s h a l e .

42

M ain Group

FENTAGONOSTYLI Moore

C r i n o i d colum ns w i t h p e n t a g o n a l o r s u b p e n t a g o n a l c r o s s s e c t i o n s .

Group PENTAGONOGYCLOPAS Moore
P e n t a g o n o s t y l i w i t h a c i r c u l a r lumen*

S e c tio n P - C - 1

D a v ie s

P e n tag o n o cy clo p ae w ith a s t e l l a . t e c e n t r a l a r e a .
xype

F - C - 1 - A.

P - C - 1 - A
P la te I I I
P e n ta g o n al c ro s s s e c tio n .
1 . 5 mm* t h i c k .
fla t,

S e c tio n

D a v ie s

F i g u r e 11
D ia m e te r 4 mm*

P e r i p h e r y p l a n e and sm o o th .

c r e n e l l a e a l o n g edg e o n l y .

C e n t r a l a re a, s t a r - s h a p e d ;

D is c s s i m i l a r .

A rtic u la te su rface

Lumen c i r c u l a r , 0 . 1 mm. w id e .

seg m e n ts o f s t a r e x t e n d t o edge o f

d is c , d iv id in g d isc in to fiv e p a r ts .
R em ark s:
7,

S pecim en fro m t h e B e l l s h a l e , C am p b ell w e l l , s e c t i o n

W a lk e r t w o n s h i p , 370 f e e t .

S e c tio n
P e n ta g o n o cy c lo p a e
d e p re ssio n s in i t .

Cheboygan C o u tn y .

P - C - 2

D a v ie s

w ith a c e n t r a l a re a w ith f iv e (c irc u la r
S e c tio n ty p e P - C - 2 - A

43

P - C - 2 - A
P la te I I I

D a v ie s

F i g u r e 12

P e n ta g o n al c ro s s s e c tio n .

D ia m e te r 4 mm.

A n n u la te,

C o lum n als

i n s e r i e s of f o u r :
1.

D is c 1 mm. t h i c k .

2.

D isc 0 . 5

mm.t h i c k *

3.

D is c 0 . 8

mm.t h i c k .

4.

D is c 0 . 5

ram.t h i c k .

O c c a s i o n a l l y a v e r y t h i n d i s c o c c u r s b e tw ee n d i s c s 2 and 3 ; and
3 an d 4 .

A r t i c u l a t e s u r f a c e f l a t , g r i l l e d a l o n g edge o n l y .

Lumen c i r c u l a r , a b o u t 0 . 2 mm. w i d e .

C en tral area f l a t .

At e a c h

a n g l e on t h e s u r f a c e a r e c i r c u l a r d e p r e s s i o n s 0 . 8 mm. i n d i a m e t e r .
R em ark s:

O c c u rs i n t h e B e l l s h a l e f

S e c tio n P - C * 3

R o ck p o rt Q uarry.

D a v ie s

P e n ta g o n o c y c lo p a e w i t h a b r o a d , sm ooth c e n t r a l a r e a . S e c t i o n
ty p e

P - C - 3 - A.

P - C - 3 - A
P la te I I I
P e n ta g o n a l c ro s s s e c t i o n .

D a v ie s

F i g u r e 13
D ia m e te r 5 mm.

A rtic u la te su r-

ia .ce g r i l l e d a l o n g t h e p e r i p h e r y o n l y , c r e n e l l a e a b o u t 0 .3 mm.
C e n tra l area f l a t ,

s l i g h t l y d e p r e s s e d be lo w g r i l l i n g , sm o o th ,

44

a b o u t 1 mm. w i d e .
a n d s m o o th .
Remarks*

Lumen c i r c u l a r ,

1 mra. w id e .

A rra n g e m e n t o f d i s c s unknown.

O c c u rs i n t h e B e l l s h a l e ,

la n a u co u n ty ,

P e r i p h e r y p la n e

E m pire to w n s h ip w e l l , Lee­

1285 t o 1290 f e e t .

S e c tio n

P - C - 4

D a v ie s

P e n ta g o n o c y c l o p a e w i t h l a r g e lu m e n s , d e p r e s s e d c e n t r a l
a r e a s an d s t r o n g l y k e e l e d d i s c s .

S e c t i o n t y p e P - C - 4 - A.

P - C - 4 - A
P la te I I I
P e n ta g o n al c ro s s s e c t i o n .
2 mm. t h i c k .

D avie s

F i g u r e 14
D ia m e te r 2 mm*

P e rip h e ry convex, s tro n g ly k e e le d .

su rfa c e concave.

C r e n e l l a e a l o n g edge o n l y .

C e n t r a l a r e a sm ooth and d e p r e s s e d .

D is c s s i m i l a r .
A rtic u la te

0 . 1 mm. l o n g .

Lumen c i r c u l a r , 0 . 1 mm.

d ia m e te r•
Remarks*

O c c u rs i n t h e C-enshaw f o r m a t i o n ,

s o u t h o f O c q u eo c ,

Presque I s l e

co u n ty .

R o ad sid e ,

1/4

m ile

45

S e c tio n P P e n ta g o n o cy clo p ae
cro ss se c tio n .

C - 5

D a v ie s

w i t h l a r g e lumen and a s u b p e n t a g o n a l

S e c tio n ty p e P -

C - 5 - A.

P - C - 5 - A D avi e s
P la te I I I

F i g u r e 15

S u b p en tag o n al c r o s s s e c t i o n .

D ia m e te r 2 t o 3 mm.

vhe a r r a n g e m e n t o f t h e d i s c s i s v e r y i r r e g u l a r .
g r i l l e d e l o n g t h e edge o n l y .
ro llin g .

A rtic u la te surface

C e n t r a l a r e a s l i g h t l y r a i s e d and

F i v e d i s t i n c t , low r i d g e s , a r r a n g e d s y m m e t r i c a l l y e x te n d

ir o m t h e r a i s e d c e n t e r t o t h e p e r i p h e r y .
d ia m e te r.

Lumen c i r c u l a r , 0 . 5 mm.

C r o s s s e c t i o n a l a r e a i n t h i s fo rm i s somewhat modi­

f i e d by t h e r o u n d in g o f t h e a n g u l a r e d g e s o f t h e d i s c s .
R e m a rk s :

A n n u late:

O c c u rs i n t h e B e l l s h a l e ,

R o c k p o rt Q u a r r y .

PLATE

I

B 'ig u r e :
1.

C - C - l - A

A rtic u la te su rface.
Column

2.

C - C - l - B

3.

C - C - l - C

C - C - 1 - D

C - C - l - E

6

.

C - C - 1 - F

7.

C - C - 2 - C

8

.

C - C - 2 - A

9.

C - C - 2 - B

10.

C - C - 3 - A

11.

C - C - 3 - B

12.

C - C - 4 - A

X 6.

X I.
X 8.

X -1 .5 .

A rtic u la te su rface
Column

X 4.

X 1.

A rtic u la te su rface
Column

X 4.

X 1.

A rtic u la te su rface
Co luran

X 5.

X 2.

A rtic u la te su rface
Column

X 3.

X 1.

A rtic u la te su rface
Column

X 6.

X 3.

A rtic u la te su rface
Column

X 4.

X 1.

A rtic u la te su rface
Column

X 3.

X 1 .5 .

A rtic u la te surface
Column

X 3.

X 1.

A rtic u la te su rface
Column

5.

su rface.

A rtic u la te su rface .
Column

4.

X 1.

A rtic u la te
Column

X 3.

X 1 .5 .

X 6.

PLATE

I

(c o n t.)

F ig u re:
13.

C - C - 2 - F

A rtic u la te su rface
Column

14.

C - C - 2 - E

15.

C - C - 4 - D

C - C - '4 - E

17*

C - C - 8 - A

18.

C - C - 4 - C

19.

C - C - 4 - B

20.

C - C - 7 - A

21.

C - C - 8 - B

22.

C - C - 8 - C

23.

C - C - 5 - A

24.

0 - C - 6 - C

X 3.

X 1.

A rtic u la te su rface
Column

X 10

X 2.

A rtic u la te su rface
Column

X 10

X 2.

A rtic u la te su rface
Column

X 5.

X 1.

A rtic u la te su rface
Column

X 6.

X 1 .5 .

A rtic u la te surface
Column

X 8.

X 1 .5 .

A rtic u la te su rface
Column

X 6.

X 0 .5 .

A rtic u la te su rface
Column

X 6.

X 1.

A rtic u la te su rface
Column

X 6*

X I.

A rtic u la te su rface
Column

X 8.

X 1 .5 .

A rtic u la te su rface
Column

16.

X 2.

A rtic u la te su rface
Column

X 6.

X 1.

X 4.

PLATE I

(c o n t.)

F ig u re:
25.

C - C - 6 - A

A rtic u la te surface
Column

26.

C - C - 6 -B

27.

C - C - 7 - B

C - C - 2 - D

29.

C - C - 9 - A

30.

C - C - 10 - A

X 10.

X 1.

A rtic u la te su rface
Column

X 6.

X 1*

A rtic u la te su rface
Column

X 5.

X I.

A rtic u la te su rface
Column

X 3.

X 1.

A rtic u la te su rface
Column

2 8.

X 1 .5 .

A rtic u la te su rface
Column

X 4.

X 2.

X 10.

PLATE

B

25

I

06

PLATS I I
F ig u re s
1.

C - C - 11 - A

A rtic u la te su rface
Column

2.

C - C - l l - B

3*

C - C - 12 - A

C - C - 2 - G

C - F - l - A

C - F - l - B

C - F - l - C

8.

C - F - l - D

9.

C - F - l - E

10.

C - F - 2 - A

11.

C - F - 3 - A

12.

C - F - 3 - B

X 5.

X 1.
X 3.

X 1.

A rtic u la te su rface
Column

X4 .

X 1.

A rtic u la te su rface
Column

X6.

X 1.

A rtic u la te surface
Column

X4 .

X I.

A rtic u la te surface
Column

X4 .

X 1.

A rtic u la te su rface
Column

X4.

X 1.

A rtic u la te su rface
Column

X8.

X 2.

A rtic u la te su rface
Column

7.

X I.

A rtic u la te su rface
Column

6.

X !•

A rtic u la te su rface
Column

5.

X 8*

A r t i c u l a t e s u rfa c e X 10.
Column

4.

X 1.

A rtic u la te su rface
Column

X 8.

X 1.

X 2.

PLATS

I I (c o n t.)

F ig u res
13.

C - F - 4 - A

A rtic u la te su rface
Column

14.

C - F - 5 - A

15.

C - F - 5 - B

C - F - 5 - C

17.

C - F - 5 - D

18.

C - F - 6 - A

19.

C - F - 6 - B

20.

C - F - 6 - C

X 5.

X 2.

A rtic u la te su rface
Column

X 5.

X 2.

A rtic u la te surface
Column

X 10.

X 2.

A rtic u la te su rface
Column

X 6.

X 1.

A rtic u la te su rface
Column

X 6.

X 1.

A rtic u la te su rface
Column

X 8.

X 1.

A rtic u la te su rface
Column

16.

X 0 .5 .

A rtic u la te su rface
Column

X 6.

X 2.

X 5.

PLATE

III

F igu re:
1.

C - F - 2 - B

A rtic u la te su rface
Column

2.

C - F - 6 - D

3.

C - F - 6 - E

C - F - 5 - E

5.

C - F - 6 - F

6.

C - F - 5 - F

7«

C - T - l - A

8.

C - P - l - A

9.

C - S - l - A

10.

C- S

- 1

- B

11.

P- C - 1

-A

12.

P- C - 2

-A

X 10.

X 1.

A rtic u la te surface
Column

X 10.

X 1.

A rtic u la te su rface
Column

X 10.

X 1.

A rtic u la te surface
Column

X 6.

X 1.

A rtic u la te surface
Column

X 6.

X 1.

A rtic u la te su rface
Column

X 8.

X 1#

A rtic u la te su rface
Column

X 4.

X 1.

A rtic u la te surface
Column

X 8.

X 2.

A rtic u la te su rface
Column

X 6.

X 1*

A rtic u la te su rface
Column

X 4.

X 1.

A rtic u la te su rface
Column

4.

X 1.

A rtic u la te su rface
Column

X 8.

X 1.

X 8.

PLATE

I I I (c o n t.)

F ig u re :
13.

P - C - 3 - A

A rtic u la te su rface

X 8.

Column

\U

X 1.

/ A

:/

.o'

14.

P - C - 4 - A

A r t i c u l a t e s u rfs te e
Column

15.

P - C - 5 - A

X 2.

'

■[

A rtic u la te su rface
Column

X 1.

X 10.
1

I

X 8.

PLAT^ I I I

'/m m

o