DIGESTIVE TRACT. 



37 



/HV 



SP 



:SV 



FIG. 39. Alimentary tract of dog- 

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

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

 spiral valve showing through ; /, liver ; 

 m, mesonphros ; /, pancreas ; r, rectal 

 gland ; s, spleen ; st, stomach. 



FlG. 40. Alimentary canal of Pro- 

 topterus, after Parker. C, cloacal 

 caecum ; G, gall bladder ; HV, hepatic 

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

 oviduct; PV, pyloric valve; R, rec- 

 tum; RD, renal (mesonephric) duct; 

 S, stomach; SP, spleen; -SF, spiral 

 valve ; F, vent. 



