GALL-BLADDER. 



243 



hepatic duct to form the ductus choledochus or common bile-duct. 

 The cystic duct, from the neck of the gall-bladder to its union 

 with the hepatic duct, is 3 to 7 cm. long, and has a diameter of 

 2.3 mm. The length of the common bile-duct depends upon the 

 point at which the cystic and hepatic ducts unite, which is not 



FIG. 137. Diagram of a segment of an hepatic lobule: 1,1, interlobular 

 portal vein ; 2, central vein ; 3, 3, intralobular capillaries ; 4, 4, interlobular 

 hepatic artery ; 5, 5, ramifications of hepatic artery, contributing to the formation 

 of the intralobular capillaries ; 6, 6, interlobular bile-duct; 7, 7, its ramifications in 

 the lobule, forming a plexus of intercellular canaliculi ; 8, 8, section of biliary canal- 

 iculi with their intercellular capillaries; 9, 9, hepatic cells; 10, 10, interlobular 

 lymphatics, receiving the intralobular lymphatics; 11, 11, 12, intralobular con- 

 nective tissue (Testut). 



uniform. The following measurements are given : 7 to 8 cm. 

 (Sappey) ; 2 to 4.5 cm. (Luschka) ; 6 to 7 cm. (Joessel). Its 

 diameter is from 5.6 mm. to 7.5 mm. 



The coats of the gall-bladder are three : serous or peritoneal ; 

 fibro-muscular, made up of fibrous tissue with plain muscular 

 fibers arranged both longitudinally and transversely, the former 

 greatly predominating ; and mucous. This last, which forms the 



