BUDS AND STIPULES. 233 
buds. The specimen examined did not show any leaves developed 
from the base of axillary buds and resembling stipules, as in 
R. levis, but that may be dependent upon a certain stage of 
growth. 
Rivina purpurascens, Schrad.—The terminal bud in the growing 
stage consists of numerous conduplicate leaves, closely crowded 
together, but not enclosing one another; the older shelter the 
younger. These leaves attain a considerable size before unfolding, 
and as they open the edges become involute and continue in this 
condition for some time while the leaf is enlarging. 
The axillary buds are protected in their early stages by an 
ovate or triangular, fleshy, deep green process that is intrapetiolar, 
inserted at the very base of the petiole, but to all appearance 
belonging to the axillary bud itself. This organ is convex on 
the face next the petiole and flattened against the axillary bud. 
It arises while still within the leaves of the terminal bud and for 
some time completely covers the axillary one. The first two 
leaves of the latter develop almost simultaneously, but one is 
really slightly in advance of the other and ultimately becomes 
distinctly alternate. These leaves are conduplicate and at first 
appear like stipules, but finally reach perfect development. 
Rivina humilis, Linn.—The leaves are smaller than in the pre- 
ceding species, densely and conspicuously pubescent, so that the 
young leaves, particularly while in bud, must derive benefit from 
the additional protection. 
The intrapetiolar seale is well developed from an early stage 
onward and is deep olive at first, becoming pale brown after 
pa me, As in the preceding species, the scales develop into 
aves. 
à he terminal bud is protected by the densely downy covering of 
er surface of the three to five exposed leaves during the 
BP of growth, and partly also by the axillary buds. 
We Ne axillary bud consists entirely of fleshy, undeveloped leaves, 
of levels even while the terminal one is only in the progress 
fleshy bud nont, A transverse section through the apex of i is 
entiated » Mb (1) one large leaf that is merely an undi ee 
than a midrib or petiole, and (2) the tip of another that is less 
down at of the size of the first. Another section lower 
consisting four or five leaves in situ, all of different sizes and 
Spondi 5 of n reniform midrib, the sides of the sinus corre- 
"8 to the commencement of the parenchymatous and 
