Freshwater Bryozoa, with descriptions of new Species. 193 
of the ovary*. In Fredericella a similar nucleated cell, Pl. II. 
figs. 4.0 & 5 e, has been observed in the appendage to the 
stomach, while the polype was yet in a very rudimentary state, as 
exhibited in the bud before alluded to. In this genus I have 
likewise seen the ovum im a considerably advanced state, in which 
also its relationship to the ovary could not be mistaken. In this 
instance the lower portion of the generative organ had dilated 
into a sort of capsule, within which the egg, Pl. II. fig. 6a & 
Pl. III. fig. 4e, was enveloped. The portion of the ovary, Pl. IT. 
fig. 6c, below it was short and thick, having the appearance of 
a pedicle, by which the egg was fixed to the side of the cell; 
above the capsule, the ovary, c, was much thinner, contracting 
suddenly upwards. This would seem to demonstrate that the 
egg is developed in the interior of the ovary. 
I have also seen what I take to be the ovum of Paludicella, but 
as it differs considerably from the egg of the other freshwater 
Bryozoa, we must not pronounce with certainty. This supposed 
egg was first observed in the cell of the dead polype; two or 
three occurred ; they were attached to the upper portion of the 
interior of the cell. Afterwards one, Pl. IV. fig. 7 e, was found 
in connexion with the living animal, and in this case was fixed 
by a delicate membranous sac, f, to the side of the cell at the 
point of attachment of the filament coming from the upper end 
of the stomach, the base of the filament being apparently sur- 
rounded by the sac. This filament then, in Paludicella, is pro- 
bably an ovary ; and if so, the egg must pass in a very early stage 
from it into the membraoas sac at its base, and there be ma- 
tured. And, judging from analogy, the other filament is also pro- 
bably connected with generation. 
In Plumatella and Fredericella however there can be no doubt 
of the ovarian character of one of the filaments attached to the 
stomach ; but the nature of the other two, Pl. III. figs. 4f& 5 
h, h, is not so easily determined. They certainly do not look al- 
together unlike muscular fibres; but from their attachments 
close to that of the ovary, and from their resemblance to it, they 
are most probably connected with the generative function. It 
may be that each filament is.a separate ovary, or that one or two 
of them is the male organ. These polypes are most probably 
hermaphrodites—at least, in all the specimens of Plumatella All- 
mant that I have examined, there was scarcely a cell that did not 
contain one egg or more. It may therefore be presumed that 
each individual is provided with male and female organs. Dr. 
Farre discovered moving bodies in the visceral cavity of Valkeria 
and some other of the marine forms, and described them as re- 
* T have also seen a similar nucleated cell im the enlarged filament from 
the lower end of the stomach of Bowerbankia. 
Ann. & Mag. N. Hist, Ser. 2. Vol. v. 13 
