Messrs. Hancock and Embleton on the Anatomy of Eolis. 187 
of the anterior ganglia between the last-described nerve and the 
median line. They all pass a good way backwards to the dorsal 
skin on each side of the median line. 
The origin, course and distribution of the six pairs of infra- 
cesophageal nerves are as follows :— 
The first pair come from the upper surface of the roots of the 
pedicles that support the gastro-cesophageal, and close to the 
buccal ganglia. The nerves are rather small, run forwards and 
apply themselves to the oesophagus, along which they are con- 
ducted to the stomach, the greater part of which organ they sup- 
ply with branches. 
The second, third and fourth arise from the margins of the 
gastro-cesophageal ganglia, are very small nerves, but can be 
traced to the cesophagus and neighbouring parts of the stomach. 
The fifth pair come out of the external ends of the buccal 
ganglia in conjunction with the third or outermost cesophageal 
collar, to which they are slightly inferior in size. The nerves and 
the collar separate at once; the nerves passing backwards and 
outwards give off each a branch that bends forwards and outwards 
and becomes lost among the muscles of the buccal mass external 
to the ganglion. The trunk then inclines towards an opening 
between the muscular bundles of the back part of the buccal 
mass, and enters that opening lying in contact with another large 
nerve that is observed to issue from the same. 
It is difficult to follow the trunk far into the intermuscular 
aperture, but as far as we have been able to trace it, it appears 
to be destined for the buccal mass and tongue. 
The sixth pair is given off from the posterior margin of the 
buccal ganglia, and shortly after becomes lost among the mus- 
cular bundles of the back part of the buccal mass. 
Of the five pairs of nerves from the commissures, two have 
already been described, viz. the first and second supra-cesopha- 
geal ; the three that remain come off from the cesophageal collars 
in the following manner. 
The pair marked « come off from the outer margin of the first 
or innermost collar near the median line. They are very minute 
nerves, and we have not succeeded in tracking them to their 
destination. 
That marked 8 is the genital and probably the cardiac nerve, 
and is an offset from the middle or slender collar, which it nearly 
equals in size, at a short distance behind its attachment to the 
anterior cerebral ganglion. It runs from this origin backwards 
and outwards to the generative organs, guided partly by the an- 
terior aorta, gains the fissure where the confluence of the ducts 
from the different parts of the generative apparatus exists, and 
