27-2 
SVEDELIUS : LIFE-HISTORY 
is double, viz., with six leaves, but nearly uniform (fig. 1). 
The number of the anthers is also always three, whereas in 
Vallisneria the perianth is always single, and commonly one 
anther is lacking. But a more remarkable difference is that 
in Enalus the filaments are particularly short, scarcely 
developed at all, and are also directed straight upwards, so 
1.—Transverse section of a male flower (15x1). 
that the three anthers stay close together in the centre of the 
flower and point vertically upwards (PI. XXIV., A, fig. 4, 5). 
In Vallisneria on the contrary—at least to judge from the 
figure and description given by Kerner (16, II., p. 130)—the 
filaments are well developed and “ ragen in schrager* Ricb- 
tung in die Luft empor.” The difference may easily be seen 
by comparing my fig. 4, 5 (PI. XXIV., A) with that of Kerner 
(16, II., p. 130). This difference is also in close connection 
Fig. 2.—Transverse section of a 
n cell (226X1). 
with the different manner in which the pollination takes 
place in these two plants. 
The further organization of the male flowers may be 
QRderstood by ref erring to the figures. The perianth whorls 
* Italicized by the author. 
