ENALUS ACOROTDES. 
*275 
asunder whereby the breadth is augmented (PI. XXIYA, 
fig. 14). Fully developed—at the stage of pollination—the 
female spathe-leaves (PI. XXIV., A, fig. 8) are narrowly 
oblong, not exceeding 2 cm. in breadth. In length they 
agree with the male spathe-leaves, but differ in their form 
and situation. A little before the time of pollination they 
curve outwards ; besides they are so stiffly keeled that both 
halves of the leaves, at least at the top, have their surfaces 
nearly pressed together. The edges of the leaf never roll 
up. By this arrangement—which perhaps is best under¬ 
stood by looking at fig. 8 (PI. XXIV., A) compared with fig. 1 
(PI. XXIV., A)—the double advantage is obtained that the 
petals are freely exposed—which, as I shall show below, is 
fundamental importance for the pollination—and also 
that the whole flower, by meanB of the wing-like spathe- 
leaves, is kept floating on the surface in a horizontal 
| position. 
; . The female flower of Enalus (PI. XXIV., A, fig. 9) has a 
double perianth of three sepals and three petals. The ovary 
: while still young is already densely clothed with rather 
large hair-like projections. The sepals are short, oval, smooth 
with entire edges. The petals are much longer, up to 3-4 
times the length of the sepals. They show a very characteristic 
I folding which certainly may be partly caused by the fact 
that the petals increase while the closed sepals still prevent 
their free development {cf. Arnoldi, 1, p. 440). The folding 
Ills partly lengthwise, partly crosswise (PI. XXIV., A fig. 9). 
While the folds in the length are two only, running at a 
rather short distance from each other parallel to the edge of 
the leaves, the cross folds are numerous, the edges of the petals 
are consequently just roughly denticulate. The tannin cells 
are present in great numbers spread all over the lamina, not 
gathered together in a few strings in the middle of the leaves 
as in the male flower. Concerning the structure of the petals 
it may be noted that the epidermal cells are provided with 
If papillae, the walls of which have the same structure as in the 
