xii PHYLUM MOLLUSCA 761 



in both the right alone appears to be functional, and the left is much 

 the smaller. The opening of the right sperm-duct of the male is 

 situated on a cylindrical prominence the penis (pen.) placed 

 close to the middle line. In the female the nidamental glands are, 

 as in Sepia, conspicuous objects when the mantle-cavity is exposed ; 

 but they are mainly situated on its posterior instead of its anterior 

 wall. 



Enteric Canal. The mouth is surrounded by a circular lip 

 beset with numerous papilla. There is a pair of jaws (Fig. 690, 

 jaw) of similar shape to those of Sepia, but much more powerful, 

 and calcined towards the tips. The buccal mass is a large rounded 

 body with thick muscular walls. On the floor of the contained 

 cavity is a large and prominent odontophore (odont.), with long 

 and pointed, curved teeth. In front of the odontophore is a large 

 bilobed soft prominence, the tongue (tong.). Behind the odonto- 

 phore, between it and the opening of the oesophagus, are one large 

 median and two lateral tongue-like prominences beset with papillae ; 

 on the inner surface of the latter are the apertures of a pair of salivary 

 glands. 



The oesophagus (CBS.) becomes dilated aborally into a very 

 spacious crop (cr.) for the storage of the food, which consists of 

 small prawn-like Crustaceans and small Fishes broken up by the 

 jaws and radula. This opens into a rounded stomach (stom.) having 

 very much the appearance of the gizzard-like caecum of Sepia. 

 The intestine (int.), shortly after it leaves the stomach, develops 

 a rounded ca3cum (ccec.) with complexly folded walls, into which 

 the ducts of the digestive gland or " liver " open. The intestine 

 does not pass straight to the anus as in Sepia, but first bends 

 round in a short coil. The ink-sac and duct of Sepia are not 

 represented." There is a very large digestive gland divided into 

 four main portions or lobes, each of which is made up of a number 

 of lobules. The ducts (" bile-ducts," b. du.), opening as above 

 mentioned into the caecum, have a series of small diverticula which 

 may represent the pancreatic appendages of Sepia. 



The ccelome consists of the pericardium and the gonocoele the 

 cavity in which the gonad is enclosed : these communicate with 

 one another by three apertures. The pericardium contains the 

 ventricle, the four auricles, and parts of the renal glandular appen- 

 dages. It communicates with the exterior by the viscero-pericardial 

 apertures. 



Heart and Vascular System. The blood-system consists of 

 the heart, the arteries and veins, and certain large spaces constituting 

 the haemoccele. The latter consists of three chief parts the 

 peristomial, peri-cesophageal, and peri-hepatic haemocceles, the first 

 surrounding the buccal mass, the second the oesophagus, and the 

 third the liver. 



The ventricle (Figs. 690 and 692, vent.) is a bilobed, transversely 



