496 THE UBINABT APPARATUS. 



applied, and on whicli they are moulded. In many ^Ms nevertheless three portions 

 more or less separated by fissures, may be recognised The Jeo-lumbar portion (so named 

 because of its constant position in this region) is the most advanced ; it is Mten the 

 larZt The middle is the narrowest ; it is turned towards the ileo-saoral region to enter 

 Klvis The posterior is contained in that cavity, and is again arger. Tliesetwo 

 Kortions are^designated as the anterior or superior pelvic and th« mfenor^o^^^^^^^^^^^ 

 pelvic portions. Their internal and superior border is often notched by a seues oi trans 



Fis. 254. 



Fig. 256. 



KIDNEYS OF THE OX. 



Fig. 254. — Eight Icidney, viewed on its upper and external face. Fig. 255. — Left 

 liidney, from its internal and inferior face ; a, Pelvis ; 5, 6, i, Branches of tlie 

 pelvis terminating in calices ; c, Ureter ; d, Kenal artery. Fig. 256. — The calices 

 in the left Itidney. The contents of the hilus, including the branches of the 

 pelvis, have been removed to show the tubercles at the bottom of these calices. 

 Only seven are visible, the others being beneath the borders of the renal fissure. 



verse fissures produced by the protrusion of the transverse processes of the sacral verte- 

 brae, as the lungs are furrowed by the projection of the ribs.'" 



The excretory apparatus is incomplete, and is only formed by the ureters, which open 

 into the cloaca, where the urine is mixed with the fseces. Only one bird, the Ostrich, 

 possesses a bladder, which is disposed in a particular manner. 



OOMPAEISON OF THE TJEINAKY APPARATUS OF MAN WITH THAT OF ANIMALS. 



1. Kidneys. — The two kidneys of Man have, like those of the smaller domesticated 

 animals, the same shape — that of a haricot bean. The average weight is about from three 

 to five ounces. Contrary to what is observed in the Horse, the left kidney is more 

 voluminous than the right, and is higher. 



The kidneys are simple externally, though their tissue is disposed in distinct lobes, 

 which number from eight to fifteen, and are composed of a Malpighian pyramid and a 



' Cwvier, ^Anatomie Comjpar^e' 2nd edition. Paris, 1836-46. 



