VERNATION. 35 
leaf-less appearance, and render the flowers so difficult 
to pluck off. 
39. With regard to the Stipules, these parts of the 
leaf are frequently absent, as in the Lilac, Pink, &c. 
while in the Rose Tree (pl. 3. f. 1. s¢.), they are large 
and united by one side to the lower end of the petiole: 
they are large, and slashed or lobed in the Heartsease 
(pl. 2. f. 4. st.), and are often mistaken for the lamina 
or blade itself, which however is narrow, and has a 
short petiole. In the Tart Rhubarb they are united so 
as to form a tube or sheath, which surrounds the stem, 
just above the part where the petiole joins it. In the 
Robinia (pl. 8. f. 5. st.), or False Acacia, the two 
short thorns placed at the bottom of the petiole, are 
the stipules of the leaf, changed into thorn-like parts ; 
and there are some Acacias which have the petioles so 
large that they resemble leaves, while the leaflets are 
often absent. 
VERNATION, OR THE MANNER IN WHICH LEAVES 
ARE FOLDED UP IN THE BUD. 
40. If leaves are examined at a very early period of 
their existence, namely, when they are just beginning 
to open in the bud, they will be found to be folded up 
in different ways: this is called vernation. The follow- 
ing are the usual forms; and in examining, the bud 
should be cut across, in order to show how the leaves 
are folded. In the Rose Tree, the leaflets will be found 
to be folded lengthways, one half upon the other; this 
is called conduplicate vernation (pl. 12. f. 9. a.), the 
margins of the leaf being folded together. In the 
