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The Brittle Branches of Salix were recently referred to by Mr.
Thomas Meehan. Ordinary wood-cells are long, and possess tapering
extremities which overlap each other. This overlapping occurs
all along the wood, about as much in one place as in another. ln
brittle willows the cells mostly end abruptly at the place where the
branch snaps off. At first thought, this might seem to be a defect in
the structure of the plant. Notwithstanding this peculiarity, such

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trees produce branches enough. The wind, weight of snow or
other forces frequently bring down the young branches. The trees
mostly grow in moist soil, frequently near streams. These branches
may take root in the soil where they drop, or be carried down
stream by the current and lodge on the shore below. With this
view, the brittleness is a very effectual means of multiplying and
distributing the species. Analogous examples are not uncommon.
The fleshy buds in the axil of the leaves of the tiger-lily separate
spontaneously and produce independent plants where they fall in
suitable places. Sempervium globiferum produces some slender
branches a foot or more in length, and these bear a couple of small
thick leaves at the end, within which are rudiments of other leaves.
These leafy tips spontaneously separate and produce new plants
where they strike soil. If my memory is not at fault, the slender
branch then dies, as is the case with the runner of a strawberry after
it produces a new plant at the end. Doubtless many similar examples
are familiar to most botanists and horticulturists.
Michigan Agricult. College, Lansing. W. J. BEAL