262 



STRUCTURE OF GLAKDS. 



Fig. 265. Lobules of the liver, superficially si- 

 tuated, divided horizontally ; a, a, intralobular 

 veins ; b, b, clefts between the several lobules, in 

 which cellular tissue, minute subdivisions of the 

 hepatic ducts of the vena portae and hepatic artery, 

 are included ; the middle portion of each lobule is 

 here in a state of congestion. After Kiernan. 



with thin parietes, from the 40th to the 50th of a line in 



diameter, and 

 capable of being 

 distended by air, 

 introduced into 

 the gall - ducts 

 with which they 

 are connected. 

 For this struc- 

 ture we have the 

 assurance of ana- 

 logy, from what 

 we witness in the 

 constitution of 

 the other glands, 

 the mode of evo- 

 lution of the li- 

 ver itself, and 

 the structure of 

 the organ in the 

 invertebrate se- 

 ries of animals ; 

 in fact, if we 

 turn to the cray- 

 fish and common 

 garden snail, we 

 find the precise 

 structure in ques- 

 tion. In the 

 cr ay-fish the li- 

 ver consists en- 

 tirely of small 

 pointed cseca, 

 clustered like 

 grapes ; in the 

 snail it is made 

 up of blind, 

 rounded, termi- 

 nal vesicles, 

 which may be 

 blown up with 



Fig. 266. The intralobular plexus of biliary ves- 

 sels, as figured by Kiernan although the injection 

 of these vessels was not so complete as it is here re- 

 presented ; d, d, two lobules divided across, with the 

 ramifications of the hepatic vein, c, a, the twigs of 

 which perforate their centres ; b, 6, b, b, branches 

 of the hepatic duct, as they take their rise from the 

 plexus of biliary vessels, which are here injected, and 

 surround the uninjected portions of the substance of 

 the lobules, d, d; c, cellular substance between the 

 lobules. 



