444 



T. J. EVANS 



thrown into longitudinal folds so that whole fish embryos pass 

 through it unrnutilated. Good serial sections of these are 

 often obtained in microtome preparations. 



The rest of the alimentary system consists of a spacious bag 

 (Text-fig. 1, g.s.) extending to the end of the body together with 

 its glandular diverticula into the cerata. In a well-fed specimen 



Text-fig. 1. 



Diagram of the alimentary system, b.m., buccal mass ; d.l., hepatic 

 diverticula ; g.fi., gastric sac ; l.g., labial glands ; n.g.s., sjiace 

 occupied by the nidamental part of the oviduct ; p.c.s., space 

 occupied by the pericardium and anterior part of the kidney ; 

 o., oesophagus : fi.g., salivary gland. 



this sac is so distended as to displace such loose structures as 

 the salivary glands and the male duct into the head region 

 above the brain and buccal mass, while the swollen ceratal 

 diverticula may give the cerata an ovoid shape. The appear- 

 ance of a common ceratal stalk observed b}' Alder and Hancock 

 and suggested as a characteristic of Calma is also a temporary 

 result of distension. On the right the sac is deeply constricted 



