LIVER OF MAMMALIA. 479 



vein enter the liver an inch above the fundus of the gall-bladder. 

 The two lateral lobes are more than double the size of the cystic 

 lobe, and of these the left is the largest. Both these lobes are 

 concave toward the small middle lobe., which they thus surround 

 and conceal. The lobulus Spigelii is of a flattened and square 

 shape, measuring 1 inch in length. The Manatee has a gall- 

 bladder. 



In the Hog-tribe the liver begins to encroach more upon the 

 left hypochondrium ; and the mass to the right of the suspensory 

 fissure is subdivided into a ( cystic ' and a right lobe, besides the 

 spigelian lobule. 



The Perissodactyles in general have a larger and more sub- 

 divided liver than the Artiodactyles, especially than the Rumi- 

 nants : no species has the gall-bladder. In the Horse this viscus 

 extends as far to the left as the right : the suspensory ligament 

 enters the fissure which defines the left lobe : the mass to the 

 right is divided by a second fissure, answering to the ( cystic ' in 

 beasts with the gall-bladder ; and a fourth small lobe is defined 

 by fissures on the under surface of the right lobe. In the 

 Rhinoceros the liver is of a dark colour, and has the usual 

 flattened form in Ungulates ; its greatest thickness not ex- 

 ceeding; 6 inches in a liver weighing 44 Ibs. : it consists of a 



o o o 



middle portion with the suspensory fissure, answering to the 

 1 cystic ' lobe, of a smaller left lobe, and a still smaller right, or 

 posterior, or spigelian lobule. The hepatic duct, J inch in diameter, 

 receives the duct of the larger portion of pancreas as it passes 

 between the coats of the duodenum, and such common duct opens 

 upon a protuberance of the mucous membrane. 1 In the Hyrax 

 the homology of the cystic lobe is better marked by the presence 

 of a cystic notch, although without the bladder, to the right of 

 the suspensory fissure : the left and right lobes have the same 

 relative proportions as in the Rhinoceros. The duct from each 

 lobe dilates on quitting it, 2 and the united capacities of these 

 receptacles equal an ordinary-sized gall-bladder ; the common 

 duct continued therefrom is 3 lines in diameter, contracts 

 gradually to the intestine, and opens therein 9 lines from the 

 pylorus. 



In the Elephant the liver is divided into two lobes, the right 

 beino* the largest: the suspensory fissure is the boundary. There 



1 V. pi. 14, fig. i. p, k. 



CLIII", p. 205. In the largest of these dilatations I found a Distoma. Dauben- 

 ton found (April) a species of the same genus in the bile-ducts of an Ass, cxn", tome 

 iv. p. 419. 



