PISTIA. 197 
portion of the leaf, the fascicles nearest the upper and under 
surfaces will be generally found completely separated by the 
development of air cells ; these fascicles are composed of lax 
woody fibre, or rather a striated mucilaginous mass of spiral 
vessels, corresponding to those of the axis, and occasionally, 
distinctly annular ones. І have found no stomata, ће pu- 
bescence is articulate, the cell at the base appears annuliform 
and larger than the rest. 
Pistia straliotes, Pl. CLXI.A. 
a, Longitudinal section of the ovarium. 
b. Longitudinal section of perfect ovule. 1 fungous testa, 
2 albumen, 3 embryo. 
c. Long section of ovarium. 
h. Ovule; e longitudinal section of ditto: i vertical view 
of the apex ditto: f. longitudinal section of the ovule, 
at a very early stage. 
d. Long section of ovarium. 
j. Embryo. : | 
k. Long section of spath, 4 column of stamens removed. 
1. Male flower, n bracts, o front of anther; p membrane of 
the anther; 7 pollen. 
m. Spath. 
q. Male flower long section. 
‘The same continued, Pl. CLXI.B. Fig. 1. 
a. Transverse section of stem, & cells forming the walls of 
the air cavities, / ducts of central fascicles. 
f. Annular vessel surrounded by dense woody fibre; d, 
transverse of radical fibre. 
g. Transverse section of stem an offset. 
i. Ditto of leaf. 
h. Ditto of petiole. 
ў. Radicle, 5 long section of radicle. 
e. Cellular tissue adjoining the air cavity. 
c.- Cuticle. 
