47 
it deserves notice that thus along another line of enquiry close 
affinity between the three genera C'haetoderma, Neomenia and Pro- 
neomenia is again demonstrated. 
The communication existing between the pericardium and the 
exterior which I found to exist both in Proneomenia and Neomenia 
(in which it appears to have been overlooked by former observers) 
was also noticed by Hansen in Chaetoderma. As to Neomenia, 
Prof. v. Grarr’s and Ray LANKESTER’s sections show the commu- 
nication to be brought about by the proximal extremity of Tuur- 
BERG’s „lateral gland”. I find this gland with its characteristic 
opening into the anal cavity (31, fig. 30) somewhat bent back upon 
itself and its internal cavity merging into the pericardium (eggbag) 
in the posterior portion of the latter. 
In Proneomenia the walls of the paired ducts leading out from 
the pericardium towards the exterior are muscular (circular mus- 
cular fibres predominating) whereas internally they are clothed with 
a strongly eiliated columnar epithelium. Moreover both of them 
carry a longitudinal prominent ridge of longitudinal fibres inter- 
woven by radial and tangential fibres with the walls of the duct 
(fig. 32, ve), which can be followed down to the point where the 
duct makes a sharp turn of 180°. Here the ridge disappears and 
at the same time the blood-lacunae which it has carried all along 
its course and which in transverse sections protrude into the lu- 
mina of the ducts (fig. 32). I do not exactly understand the sign- 
ifieance of these blood containing ridges; perhaps the suggestion 
which I venture to offer, may afterwards be confirmed, viz. that 
they are merely posterior long and thin blind prolongations of the 
heart. No communication with other bloodearrying tissues, situated 
more backwards, could in any way be demonstrated. 
After having made the sharp turn just mentioned, the ducts dd’ 
follow their course without any noticeable change in their appear- 
ance, up to the point where they communicate with the much 
more massive structures AR A’R’ upon which they rest and which 
answer to TULLBERG’S so called „lateral glands”’. Only it is evi- 
dent that the more they approach this point of junction the less 
