DIGESTIVE TRACT. 



37 



?HV 



fPV 



.-.SV 



Fig. 39. Alimentary tract of dog- 

 fish i^Acanthias'), a, dorsal aorta ; b, 

 bile duct ; //, heart ; i, 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 

 caecum; C, gall bladder ; HV, hepatic 

 vein ; L, liver ; O, oesophagus ; CD, 

 oviduct ; P V, pyloric valve ; P, rec- 

 tum; PD, renal (mesonephric) duct; 

 S, stomach; SP, spleen; SV, spiral 

 valve ; V, vent. 



