VERNATION OR PRAFOLIATION. 155 
ment of the leaves and the form of certain parts of the stem, yet 
it is not possible at present to deduce any general laws regulating 
the relations between them. 
3. ARRANGEMENT OF THE LEAVES IN THE Bup, OR VERNA- 
T1on.— Having now described the general arrangement of leaves 
when in a fully formed and expanded state upon the stem or 
branch, we have in the next place to allude to the different 
modes in which they are disposed while in a rudimentary and 
unexpanded condition in the bud. To these modifications the 
general name of Vernation (the spring state), or Prefoliation has 
been applied. Under this head we include :—1st, The modes in 
which each of the leaves considered independently of the others 
is disposed ; and, 2nd, The relation of the several leaves of the 
same bud taken asawhole to oneanother. In the first place we 
shall consider the modes in which each of the leaves considered 
separately is disposed. We arrange these again in two divi- 
Bie 294. Fie. 295. Fie. 296. Fig. 297. Fic. 298. 
Fig. 294. Vertical section of a reclinate leaf. Fig. 295, Transverse section 
of a conduplicate leaf. Fig. 296. Transverse section of a plaited or pli- 
cate leaf, Fig. 297. Vertical section of a circinate leaf. Fig. 298. 
Transverse section of a convolute leaf. Fig. 299. Transverse section of 
a revolute leaf.—— Vig. 300. Transverse section of an involute leaf, 
sions :—I1st, Those in which the leaf is simply bent or folded ; 
and 2nd, Those where it is rolled. Of the first modification we 
have three varieties :—Thus, Ist, the upper half of the leaf may 
be bent upon the lower, so that the apex approaches the base 
( fig. 294), as in the Tulip-tree, it is then said to be reclinate or 
inflered ; 2nd, the right half may be folded upon the left, the 
ends and midrib or axis of the leaf remaining immovable (jig. 
295), asin the Oak and Magnolia, when it is called conduplicate ; 
or, 3rd, each leaf may be folded up a number of times like a 
fan (fig. 296), as in the Sycamore, Currant, and Vine, when it 
is plaited or plicate. Of the second modification we have four 
varieties :—1st, the apex may be rolled up on the axis of the 
leaf towards the base, like a crosier (fig. 297), as in the Sundew 
and Ferns, when it is circinate; 2nd, the whole leaf may be 
