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4 CEPHALOPODA: 
parts of each lateral heart, having no connexion with their 
cavities. 
The organs of generation are situated at the bottom of the 
sac. Those of the male consist of vesiculee seminales, ter- 
minating in a common opening, the sides of which are slightly 
produced into a tube; those of the female consist of two ova- 
ries, terminating each in an oviduct. 
The ink-gland is composed of a spongy substance, filled 
with a black liquor, and covered by an integument, which ter- 
minates anteriorly in a tube, more or less extended in the dif- 
ferent genera. ‘This gland is imbedded in the lower surface of 
the liver in Polypus; placed under the liver in Loligo and 
Sepiola* ; and is situate before the liver in Sepia. Rondele- 
tius, Monro, and other anatomists, believed this gland to have 
been the gall-bladder, but its structure and functions totally 
disprove this notion. ‘The contained liquor is subject to the 
will of the animals ; they discharge it when entangled in the 
nets of the fishermen, who maintain that they do the same in 
the sea, for the purpose of obscurmg the water around them 
when pursued by their enemies. When evaporated, it has all 
the general properties of Indian or Chinese Ink, which is said 
to be prepared from an animal of this class. 
The head is placed on the anterior part of the body, and 
projects beyond the opening of the sac. ‘The mouth contains 
a tongue, bristled with tubercles. The eyes are extremely 
complicated in their structure ; and although compound, they 
present a vast difference from those of the animals of the ver- 
tebrose type. The hinder aspect of the eye exhibits a vast ex- 
pansion of nerves, which unite into a very large ganglion, from 
which the optic nerve arises and passes through a cartilage, 
which I will presently describe, to join the anterior mass of the 
nervous system, named the brain. 
At the base of the feet posteriorly is situated a cartilage, 
concave in front and convex behind; having its centre per- 
forated, for the passage of the cesophagus or gullet. Plate I. 
fig. 6, 7, Ap. CE. 
Within the convexity of this cartilage is situated the brain, 
* In Sepiola this gland is bilobate. 
