ALIMENTARY SYSTEM. 



407 



non-glandular, and those of the second type are often somewhat 

 eye-like, with pigment layer, reflector, lens, and diaphragm, or with 

 some of these structures. 



Alimentary system. The cuttlefish eats food which 

 requires tearing and chewing, and this is effected by the 

 chitinous jaws worked by strong muscles, and by the 

 toothed radula moving on a muscular cushion. The mouth 

 lies in the midst of the arms, bordered by a circular lip, and 

 opens into a large pharynx or 

 buccal cavity (cf. the snail). The 

 narrow gullet passes through the 

 ganglionic mass, and leads into 

 the globular stomach, lying near 

 the dorsal end of the body. The 

 stomach is followed by a caecum 

 or pyloric sac, and the intestine 

 curves headwards again, to end 

 far forward in the mantle cavity. 

 There do not seem to be any 

 glands on the walls of the food 

 canal ; the stomach has a hard 

 cuticle ; the digestion which takes 

 place there must therefore be 



due to the digestive juices of the ~ f ., 



7-\f i_ A.-L. FIG. 218. Diagram of the 



glandular annexes. Of these the structure of Sepia. Mainly 



most important is usually called after Pelseneer. 



the liver; it is bllobed, and lies a., Eight short arms around mouth; 



in front of the stomach, attached 



to the oesophagus. Its two ducts 



conduct the digestive juice to 



the region where the stomach, 



" pyloric sac," and intestine 



meet; and these ducts are 



fringed by numerous vascular 



and glandular appendages, which 



are called " pancreatic," and arise from the wall of the 



unpaired portion of the nephridia. Far forward, in front 



of the large digestive gland, lie two small white glands 



on each side of the gullet, with ducts which open into the 



mouth (cf. the t salivary glands " of the snail). A diastatic 



ferment has been proved in the salivary secretion of 



/.., one of the two long arms; 

 ., beak of the mouth ; e.g.* cere- 

 bral ganglia, with commissures 

 to the others; E. t eye; -., 

 gullet ; d.g.) digestive gland (the 

 " salivary glands " are not repre- 

 sented) ; si., stomach ; a., anus ; 

 sA., shell-sac with sepiostaire ; 

 k., kidney; JR., reproductive 

 organ; br.h., branchial heart; 

 ., a gill; *.., ink-bag; m.c., 

 mantle cavity; yC, funnel. 



