506 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
the intestine, being prevented from entering into the 
spiral caecum by the folds of the wall in this region. 
(7) In the intestine digestion is finished, as some 
proportion of the digestive fluid enters here. This region 
is, however, chiefly that of absorption. After this, the 
waste matter passes up to the anus and is ejected. 
The Ink Sac, or anal gland of Eledone is a long, 
somewhat pear-shaped gland, which opens into the dorsal 
wall of the rectum, on a slight papilla, very near the 
anus (Pl. IV, fig. 30, Z. p.). It is a much less developed 
structure than the ink sac of the Decapoda, and, unlike 
the latter, lies embedded in a groove on the ventral surface 
of the liver, in a median position (Pl. VIII, fig. 32). To 
expose it, the visceral envelope, and then the common 
iridescent membrane round the liver and ink sac, must 
be removed. Its dorsal wall lies in close contact with the 
ventral epithelial wall of the liver. ‘When the enveloping. 
membranes have been removed, the ink sac shows as a 
dull metallic dark-blue organ. Great care must be 
taken not to cut the wall, for the thick viscous 
secretion is exceedingly hard to get rid of, and stains the 
dissection deeply. The nerves should be traced before 
removing the visceral envelope. They come from two 
sources in Sepia, and probably also in Eledone (Girod). 
However, only those from one source have been followed 
out, 1.e.:— 
(1) The visceral nerves running over the liver, in the 
neighbourhood of the ink sac, send several branches 
inwards, which end in its walls (Pl. VIII, fig. 31, 
1,8, N,). Near the posterior end of the sac. a specially 
large nerve runs in from each visceral trunk, and this, 
after pursuing a downward course until it meets the 
artery and vein of the ink sac, enters the gland along 
with them (fig. 31, Z.S./.). 
