1 
hg. the right | half of the hermaphrodite gland (paired in 36, 
hg’. the left coalesced in the median line in 37, separated 
again into the two eiliated ducts in 38. 
ds. the dorsal bloodsinus. 
Cds. the heart. 
Per. the pericardium. 
vs. the ventral bloodsinus. 
I. the intestine. 
Rec. the rectum. 
F. the ventral furrow with foot-fold. 
AA’, dd’, EE’, RR’, transverse sections of the parts similarly 
lettered in fig. 46. 
Mb, Mb’. as in fig. 32. 
PLATE IV. 
Fig.40. Diagram of the nervous system. 
CG. cerebral ganglion. 
slg. sublingual ganglia. 
APG. anterior pedal ganglia. 
PPG. posterior pedal ganglia. 
PVG. posterior lateral (visceral) ganglia. 
sl. sublingual connectives. 
epc. cerebropedal connectives. 
pe. longitudinal pedal nervestems. 
la. » lateral > 
The pedal nerves are united by regular transverse commissures 
metamerically situated; the posterior one is considerably thicker 
than the others. 
The pedal nerves are moreover united with the lateral nerves by 
another set of transverse commissures. 
Other nerves directed dorsally originate from the lateral nerve-stems, 
The greater portion of special nerves originating from the cere- 
bral, posterior pedal and posterior lateral ganglia are not indica- 
ted in the figure. Whether the latiter are posteriorly united by a 
commissure above the rectum cannot with certainty be made out. 
Fig. 41. Tranverse section through the cerebral ganglion showing a faint tend- 
I 
% 
} 
ency towards division into two symmetrical lateral halves. 
N. the fibrous centre. 
cc. peripheral nerve-cells. 
on. nerves springing from the ganglion, 
