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and proportions; except that the color was creamy-white, marked 
with purplish dots. They were generally somewhat flattened on 
the side from which the lateral bud grew at the next lower node, 
which might indicate that the growth was directed to the develop- 
ment of the bud at that point rather than into that portion of the 
tuber in line with and beyond it. 
Their texture is crisp, and it cuts with that peculiar grating 
which we hear and feel while cutting a raw potato with a thick 
knife; and which is doubtless owing, as Prof. Halsted has shown 
with relation to the winter buds of trees, to the presence of large 
quantities of starch stored during the growing season, for the rapid 
development of the embryo leaves in early spring, before they are 
capable of assimilating their nourishment. 
There are at least two kinds of buds shown at the tubers; 
First, lateral leaf buds, developed at the nodes; and secondly, ter- 
minal buds, which contain an embryo vine. They are not uniform 
in size; the largest of the former measured five and one-half 
inches in length, and consisted of a single petiole surmounted by 
an involute blade two inches in diameter; the whole completely 
enveloped by a whitish, brittle succulent sheath, the edges of 
which overlap. 
We obtained some specimens in which growth had extended 
just beyond the full capacity of the sheath, and it had been torn 
completely asunder below the blade, both portions having turned 
black. 
The severed part would doubtless have continued to envelop 
the blade, and it would have been carried up through the mud by 
the lengthening petiole—as the calyptra of Musci is borne up on 
the apex of the capsule—and when its office of protection shall 
have been fulfilled the unfolding leaf will cast it aside. 
_The terminal buds are shorter and thicker than the others, and 
include a portion of the future vine. An internode and node, to- 
gether with its young leaf, are all well formed; also a growing 
point beyond, and, like the leaf buds, they are protected by a 
similar sheath. 
_ We also obtained the black shrunken shells of old tubers, from 
which all the nutriment had been drawn, which, with contiguous 
portions of the vine, were lifeless. 
