THE SKATE. 49 



and superior mesenteric arteries (Fig. 20, d, s.m) towards 

 the left, and the wide thin-walled portal vein (Fig. 16, p) 

 between them. 



Running parallel \vith these vessels is also a transparent thin- walled 

 lymphatic vessel, from which many of the chief lymphatics can be 

 injected. 



94. The gall bladder (Fig. 15, g.b), a greenish or 

 yellowish transparent sac, partly imbedded in the liver 

 between its right and middle lobes. 



r.LJ 



c.b.d 



FIG. 15. Raja nasuta. The gall bladder and bile ducts (half nat. 

 size). 



c.b.d, common bile duct: c.d, cystic duct : g.b^ gallbladder: l.h.d, 

 left hepatic duct : rJi.d, right hepatic duct. 



XVII. Carefully dissect away the peritoneum from the 

 bile duct : make a small aperture in its wall, in- 

 troduce a blowpipe and inflate : the gall bladder 

 will be distended : trace the duct in both directions 

 and make out 



done separately : the femoral and ilio-hoemorrhoidal veins also often 

 escape being filled. In a preparation for demonstrating purposes it is 

 advisable to colour the plaster of Paris used for injecting the dorsal 

 aorta with vermilion or carmine instead of French blue. 



