Messrs. Hancock and Embleton on the Anatomy of Kolis. 185 
and seems to present a small ganglionic enlargement. We have 
numbered them in the order in which they occur, commencing 
at the median line in front. 
The first and second pairs, very minute, come out of the un- 
der surface of the anterior commissure of the first or cerebral 
ganglia, and pass to the skin on each side of the median line 
before and behind the dorsal tentacles. 
The third pair, large nerves, come out of the first cerebral 
ganglia at their upper surface, and near the middle of their an- 
terior border ; they pass forwards, upwards and downwards to the 
roots of the dorsal tentacles, within which each suddenly swells 
out into a remarkable ganglion, e, of an irregularly oval form, 
which, at its upper end, divides into three or four processes, each 
giving off nerves to be distributed for the supply of the whole 
tentacle. This pair we look upon as the special nerves of smell- 
ing, for reasons which will be adduced hereafter, and as endowing 
the tentacle with the power of ordinary sensation likewise. If 
this view be correct, then the small branches passing from the 
ganglion to the sentient surface of the tentacles are properly to 
be designated olfactory nerves, and the thick pedicle supporting 
- the ganglion and connecting it with the cerebral ganglion, olfac- 
tory tractus. 
The fourth and fifth pairs, considerably less than the third, 
arise also from the anterior part but under surface of the same 
ganglia, close together, and just outside of the third. The fourth 
runs forward to the outer lip before giving off any branches ; 
after that it divides and subdivides minutely, and goes to supply 
the outer lip above and below. ‘The fifth runs forward and 1s 
distributed to the skin of the head and between the dorsal ten- 
tacles, but does not give off such numerous branches as the pre- 
ceding nerve. 
The sixth, one of the largest nerves in the body, comes out of 
the external anterior angle of the ganglion, and after a short 
course outwards and forwards bifurcates. The two branches are 
about equal in size: one passes into the oral tentacle, divides into 
two branches which subdivide and supply the tentacle; the other 
runs forward, and then inclines mwards towards the median 
line, and subdivides into many twigs which are distributed upon 
the roof of the channel of the mouth. 
The seventh and eighth are minute nerves which issue from 
the outer margin of the ganglion just behind the sixth. They 
take a straight course outward and pass into the skin of the side 
of the head. 
The ninth is a large pair, coming out of the same ganglion 
just behind the preceding, and running outwards and forwards 
gives off a twig which goes to the muscles attaching the buccal 
