KANGAROOS AND WALLABIES. 



Gall Bladder and Ducts. — The gall bladder is placed 

 in the cleft in the cystic or mesial lobe, and owing to the 

 projection to the right of the large left lat. lobe it is 

 usually only seen partly from the visceral aspect, though 

 projecting freely on the diaphragmatic face. As a rule 

 it is best examined on the visceral aspect by removing the 

 right portion of the left lat. lobe. It may be described 

 as a somewhat rounded sac, 4-5 cm. long, with a greater 

 mobility than the human bladder. Its ventral, two-thirds, 

 are completely invested by peritoneum, while the dorsal, 

 third, is less mobile, being invested on the under surface 

 and sides only, and attached to hepatic substance above. 

 From the dorsal extremity of the gall bladder the Cystic 

 Duct, 2-2.5 cm. in length, passes, lying in a groove — the 

 continuation of the gall bladder cleft — between the two 

 portions of the mesial lobe. It is joined at its termina- 

 tion in the portal interval by the Hepatic Ducts, and be- 

 comes the Common Bile Duct. The portal interval, or 

 fissure, which corresponds to the region where all the 

 lobes meet, is placed between the right cystic and right 

 lateral lobes dextrally, and the left lateral and spigelian 

 on the left, 



Hepatic Ducts. — On the left side the left hepatic 

 trunk is formed by the union of two branches — one from 

 the left cvstic or mesial, and the other from the left 

 lateral lobe; near its junction with the cystic duct it re- 

 ceives a branch from the spigelian lobe. On the right 

 lobe main trunks are noted — the smaller ventral one from 

 right mesial or cystic lobe, and the larger more dorsal 

 branch from the right lateral lobe. 



Co unit on Bile Duct. — This is formed by the junction 

 of the cystic and hepatic ducts, and passes down with the 

 hepatic artery and portal vein — the vein lying dorsally 

 as in the human liver— between the lobus spigelii, on the 



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