BUDS AND STIPULES. 243 
The third pair of stipules (fig. 66) are slightly unequal, narrowly 
ovate or lanceolate, membranous, and more faintly nerved than 
the previous pair. The outer stipule envelops about two-thirds 
of the bud, including its fellow stipule and the leaf. The latter 
is ovate-elliptic and folded over the younger members of the bud 
asarule. The fourth pair of stipules and their leaf (fig. 67) are 
sometimes very similar to the preceding set, sometimes very much 
smaller. This difference is apparently due to the relative vigour 
of the axis bearing them. 
The descriptions and sketches were made from buds just 
bursting, about the middle of April. 
Betula alba, Linn.—The winter- bud as it appears about 
the beginning of April is ovoid-oblong, obtuse, glabrous, or 
having a few cilia at the margins of the scales, and deep brown. 
The scales are in pairs, and consist really of stipules. The outer 
two or three pairs have no leaves, and one or two of the pairs 
are coriaceous. 
The first pair are slightly unequal in length, and do not overlap 
at any point nor surround the whole of the bud, being situated 
partly on one side. The second pair, when partly spread out, are 
almost semiorbicular, rounded at the apex, and slightly unequal 
in length, the inner one being the longer and overlapped at the 
base by its fellow at both edges. They cover a considerable 
portion of the bud, owmg to their width. The third pair are 
t. long as the bud, covering the whole of the younger members and 
overlapping at their edges. They are more membranous than either 
4 she one or two preceding pairs, and are more or less furnished 
with a viscid gum. They are also slightly narrowed at the base. 
he fourth pair are more decidedly boat-shaped than the 
Previous one, but are still imbricate. 
The first leaf oceurs in connection with the tbird or fourth pair 
“stipules, but entirely inside of and covered by them. It is 
thomboid, acute, shortly petiolate, serrate, penni-nerved, with 
Scending nerves, thinly pubescent, glandular and viscid in bud, 
and concave, 
The fifth pair are somewhat smaller than the fourth, but 
eiherwise similar, as is their leaf. Its form is doubtless due to 
ie abrupt arrest of the younger members of the bud; for the 
len and fifth pair of stipules, together with the first and second 
he belonging to them respectively, are greatly m advance 0 
e that follow. The sixth pair of stipules and the younger 
