INTERNAL ORGANS OF GENERA TION 



41 



uterus by corresponding veins, which are more numerous than the arteries, 

 and are capable of great distention. They have no valves. In animals 

 which have bred frequently, the vessels are greatly enlarged and very 

 flexuous ; indeed, from an early period the arteries are remarkable for 

 their large size, their tortuous course, and their frequent anastomoses ; 

 while the considerable calibre of the veins, which have no valves, is as 

 conspicuous as the complex networks they form. 



The lymphatic vessels issuing from the organ are as remarkable for their 

 large size as their number ; they all proceed towards the sub- lumbar 

 region. 



The nerves are derived from the small mesenteric and pelvic plexuses. 



Differences. 



Cow. 



The uterus of the Cow, with regard to its general disposition in the 

 pelvic and abdominal cavities, does not offer any striking differences 

 from that of the Mare, except that the body is short, and it does not 

 extend so far into the latter cavity. If the uterus was perfectly horizontal, 

 a transverse line drawn across the abdomen, in front of the external angle 

 of the ilium, would be exceeded to the extent of some one and a half to 

 two inches by the extremities of the cornua ; so that if the animal were 

 placed on its back, the uterus would only be found to reach to the fourth 

 or fifth lumbar vertebra. 



With regard to shape, however, the uterus of this animal offers some 

 noteworthy features. For instance, the concave curvatures of the cornua 

 look downwards, whereas in the Mare they are in the opposite direction ; 

 though in both the broad ligaments are attached to this concavity. The 

 consequence is, that in the Cow, if the uterus be considered as freely 

 suspended in the cavity of the abdomen, the extremity of the horn is 

 twisted outwards and upwards ; while its base near the body of the organ, 

 although drawn in the same direction by the ligaments, yet retains its 

 position, being firmly maintained in it by the body of the uterus, which 

 also receives the insertion of the broad ligaments on its lower plane. 

 This insertion causes the uterus to project above them ; while in the 

 Mare, in which the ligaments are inserted at the upper part of the body, 

 the uterus projects below them. In the Cow these ligaments are very 

 extensive, particularly at their anterior border, and widely separated from 

 one another in front near their lumbar attachment, which is prolonged as 

 far as the flank. The ligaments, taken as a whole, may be compared to 

 a triangular sheet, one angle of which is fixed to the floor of the pelvis, 

 and the other two to the tuberosities of the ilia ; on this sheet rests the 

 body of the uterus and a portion of the cornua. 



The cornua are thin and tapering at their anterior extremity, and the 

 body is short and narrow ; while the interior of. the uterus is not so ample 

 as in the Mare. Here it offers a peculiarity which is not observed in the 

 latter animal, the carnivora, nor the Pig, in the presence of rounded 

 smooth prominences, named cartmcles or cotyledofial processes {placefitce 

 uterince), which increase in number with the size of the species. These 

 maternal cotyledons are most numerous in the cornua, and few and small 

 in the body of the uterus ; in volume they are about the size of a pea or 

 haricot-bean in calves ; at a later period they have acquired the dimen- 



