THEIR FORMS AND FUNCTIONS. 509 
small ovate bracts, adpressed to the stem till the buds in their 
axils push them away. 
In Beaumontia the bud is protected by the older leaves in 
succession. They are sessile while in bud. The base of the 
petioles is connected by a rim across the stem, and there is also 
a ring of subulate glandular processes surrounding the axis, 
which, however, can hardly be regarded as stipules. The axillary 
buds are protected by the broad and thickened bases of the 
petioles. 
ASCLEPIADEE. 
In the bud each leaf has its edges opposed to, and in contact 
with, those of its fellow, so as to cover the bud completely. The 
apex spreads out first, the rest remaining erect or nearly so for 
some time, thus helping to protect the terminal bud. Vincetoat- 
cum officinale, Moench, has the petiole deeply channelled above, 
slightly dilated at the base, and inserted on a pedestal, which is 
broader and with its fellow nearly encircles the stem. The base 
of the lamina is furnished with glands, which fall away as the leaf 
develops. 
LOGANIACER. 
The leaves of Buddleia are opposite and connected at the base 
by a transverse line upon the stem, rarely by herbaceous stipules 
as in the case of B. awriculata, Benth. (fig. 6). In this species the 
stipules are interpetiolar, connate into one suborbicular piece, 
and strongly revolute at the edges, making them convex above 
and deeply concave beneath, almost like the cap of the calyx of 
Scutellaria, 3°5 mm. wide, projecting about 2 mm. from the stem, 
and of the same colour and texture as the leaves, pubescent above, 
and hoary with a fine adpressed tomentum beneath, but similarly 
hoary all over when quite young like the expanding leaves. 
The petioles are deeply channelled above and dilated at the 
base, so that they protect the axillary buds in their earlier stages. 
When the leaves are just expanding, the petioles are merely con- 
nected at the base by a slightly elevated rim, or, in other words, 
they are slightly connate. The stipular outgrowth develops as 
the leaves gradually attain their full size, so that it is functionally 
of no importance either in protecting the terminal or the axillary 
buds. This is done by the leaves themselves. The latter are flat 
in bud and closely applied face to face, protectIng the terminal 
bud, and as they are decussate, the edges of the next younger 
