50 
is a simple fissure in its wall, and above it the kidney detaches 
a lobe which becomes more and more narrow and lastly com- 
municates with the pericard. The latter is rather small, as is the 
heart too. Its place is somewhat in front of and above the genital 
opening, thus on the right side, and close outside the intestine. 
The nervous system corresponds to the description of the same 
in Runcina coronata given by Vayssiére (1883) and in R. capre- 
ensis (Mazzarelli 1893), thus showing two visceral ganglia, with- 
out direct connection with each other. 
Opaline giand. Beneath the anus a small pore appears, 
being the outlet from a rounded sac, otherwise entirely closed and 
lined with a thin epithelium. This sac 
contains 7 date-like corpuscles attached 
with their anterior ends to the front 
wall of the sac and freely projecting 
into its interior. The corpuscles prove 
to be glandular formations. They con- 
sist of an outer cutaneous sheath made 
up by two cell layers and forming a 
fold from the anterior wall of the sac, 
and an inner bottle-shaped acinus with 
a narrow efferent canal opening by a 
terminal pore; the walls of this canal 
are similar to those of the sheath thus 
Fig. 9. Rimcineiia zelandica n. sp., proving the origin of the glandula by - 
seclion through one corpuscle of 
the anal (opaline) giand. x 300. means of invagination (text-ng. 9). The 
bottom part of the giand is formed by 
large glandular cells with median nuclei and vividly stained con- 
tents (by haematoxylin); among them narrower cells with small 
apical nuclei and unstained contents appear. The small cells pre- 
dominate, and the large ones disappear, towards the canal. 
This giand is cerfainly homologous with the so called opaline 
giand in Åplysia and other genera (also named ‘‘grape-shaped” 
giand or glandula ofBohadsch; cf. M a zz a r e 11 i 1893 a), which 
has become dislocated together with the whole anal tract, and 
further peculiarly specialized and modified by the folding of the 
walls of the primarily simple glandular sac. 
