DIGESTIVE TRACT. 



37 



?HV 



SP 



PV 



sv 



R 



FIG. 39. Alimentary tract of dog- 

 fish (Acanthias}. a, dorsal aorta ; b, 

 bile duct; //, heart; /, intestine, the 

 spiral valve showing through ; /, liver ; 

 m, mesonphros; /, pancreas; r, rectal 

 gland ; s, spleen ; st, stomach. 



FIG. 40. Alimentary canal of Pro- 

 topterus, after Parker. C, cloacal 

 cgecum ; G, gall bladder ; ///*, hepatic 

 vein; Z, liver; O, oesophagus; OD, 

 oviduct; P\\ pyloric valve; /*, rec- 

 tum; RD, renal (mesonephric) duct; 

 S, stomach; SP, spleen; SV, spiral 

 valve ; V, vent. 



