40 
is the passage of eggs from the genital gland into the cavity of 
the pericardium (7, Pl.IV, fig. 3). He never found blood in the 
pericardium, but saw that the ova were pushed into it along a 
passage between the dorsal vessel and the rectum. About the 
significance of this phenomenon for the interpretation of different parts 
of the genital apparatus he makes the following remarks: 
„Now if the pericardium is the way by which the genital 
products leave the body, which supposition may be adhered to, 
on account of the observation recorded in the figure, then these 
genital products must be carried further towards the infundibulum 
by the ducts of the two glands alluded to, and in this case it ap- 
pears most probable that the glands in question are mucus-glands. 
Their cellular coating however gives no support to this view, nor 
have I ever seen mucus inside them. It is nevertheless certain 
that they are not branchial sacs as v. GRAFF will have it; they 
are in no communication with the branchiae. v. GRAFF says about 
the cells that their free margin is visibly badly preserved: denn 
das stark granulöse Protoplasma war hier diffus und die Zellen 
ineinander geflossen. Ich kann nicht sagen ob wir es schon hier 
— wie zu vermuthen ist — mit einem Flimmerepithelium zu thun 
haben. This might perhaps be more favourably interpreted as 
showing a secretion of mucus to be the normal function of these 
cells.” 
After this recapitulation of the different statements respecting the 
genital apparatus of Neomenia and Chaetoderma, it is time to pass 
on to the description of the facts as they are found to exist in 
Proneomenia sluiteri. 
The generative system of Proneomenia is wholly symmetrical. 
It consists of: 
a. the generative gland, which is situated along the whole length 
of the body and internally applied against the dorsal portion of the 
body wall, 
b. the cavities and canals through which the genital products 
are conveyed to the exterior and the accessory secreting glands. 
The latter are found in the posterior extremity of the animal. 
