45 
at least in the vieinity of both the pairs of openings of the anterior 
and posterior duets. Whether this epithelium really coats the whole 
cavity or whether its walls are partly only membranaceous I cannot 
with certainty decide, although I much incline to the latter view. 
The cavity contained a curious clot, which upon examination 
proved to be a number of eggs imbedded in a common matrix ‚the 
latter being in all probability part of the substance secreted in 
the hinder division of the hermaphrodite gland, and noticed above. 
Although sections could not be made to settle this definitely, yet 
the external appearance of the two substances is so similar as 
to leave but very little doubt as to their identity. This would 
prove that the latter hypothesis put forward, viz. that the substance 
is intended to bind the eggs together at the time of their deposi- 
tion is the more acceptable one. In none of the ova contained in 
this clot had segmentation set in; they appear to be in a normal 
condition and on their way to the exterior. It is a different case 
with a certain number of other eggs, which are separately contai- 
ned in the same cavity, applied against its wall. In most of these 
segmentation has commenced, and only a few of them have remai- 
ned intact. None of them are cunnected together by an interve- 
ning substance. In the hermaphrodite gland, close to the posterior 
extremity, eggs in which segmentation has commenced also appear 
to be of rather frequent occurrence. I] noticed a number mixed up 
among other ova not yet cleaving. It must either be inferred from 
this that normally fecundation takes place in the ovary by sperma 
which is derived from another individual and which ascends all the 
way through the genital passages (v. Inerıne (13) describes a 
similar fecundative arrangement for the Chitonidae) or that these 
cases of segmentation are only of secondary importance, and cau- 
sed by a chance meeting of ripe ova and sperma of the same in- 
dividual. ° I rather incline to the latter view although fully recogn- 
izing that only by numerous and accurate observations on the 
eycle of the reproductive functions in the living animal can the 
question be definitely put beyond doubt, as to whether the eggs nor- 
mally go through their first developmental stages inside this cavity. 
