THE ORGANS ANNEXED TO ABDOMINAL DIGESTIVE CANAL. 



509 



in the iutervals of digestion, the bile, instead of flowinp; directly on to the intestinal surface, 

 passes into the gall-bladder by the cystic duct, and tiiere accumulates. When digestion 

 commences .ig dii, this reserve of bile is thinwii into the ductus choledochus by the contraction 

 of the muscular fibres of the cyst, and by the pressure of tiie abiloiuinal viscera; it meets that 

 which comes directly from the liver, and witii it is carried tn the duodenum. 



We will now glance at the particular arningement of this vistus in each species. 



In the Ox, the liver is entirely confined to the right diaphragmatic region. It is thick, 

 voluminous, and scarcely notched at its periphery ; so that it is (liflScult, if not impossible, to 

 distinguish three lobes in it. In Fig. 302, this excretory apparatus is represented, the lobus 

 Spigelii alone being detached from the mass of the organ. The gall-bladder, fixed towards 



LIVER OF THE DOG, WITII ITS EXCRETORY APPARATUS. 



D, Duodenum and the intestinal mass ; p, pancreas ; r, spleen ; e, stomach ; /, rectum ; R, right 

 kidney j B, gall-bladder; ch, cystic duct; F F, liver; f', lobe of the liver, prepared to show the 

 distribution of the vena portse and hepatic vein ; VP, vena portse ; vh, hepatic vein ; d, diaphragm; 

 VC, vena cava ; 0, heart. 



the superior extremity, is nearly always floating; near its neck it reeeives the insertion of 

 several large conduits, which come directly from the upper part of the liver. The ductus 

 choledochus opens alone at a great distance from the pylorus; Colin has found it to be 24^ 

 inches in one cow, and 29J inches in another. In the Sheep and Goat, the form and position 

 of the liver differs but little from that of tiie Ox. The ductus choledochus, however, unites 

 with that of the pancreas, and terminates at from 12 to 16 inches from the pylorus. 



In the Camel, the liver has the same arrangement as in the other Rumiuants, except that 

 Its posterior face Is divided, lo'.iulated, and much reticulated. 



In the Pig, the liver has three well-marked lobes; the middle carries the gall-bladder 

 The ductus choledochus opens alone at 1 or 1^ inches only from the pylorus. 

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