244 ANATOMY OF THE ABDOMEN. 



tually stays the fluid from returning upon the kidneys. 

 Less urine is formed in summer than winter; for when 

 perspiration has robbed the blood of its watery particles so 

 little urine is passed, as to have led to a supposition that a 

 dangerous obstruction existed. It is also to be observed, 

 that, in our present state of veterinary knowledge, we are 

 not able to obtain many pathognomonic hints from the 

 various modifications of urine. It is true that, when puru- 

 lent, we are aware that ulceration is present in some of the 

 passages ; and when ropy, that mucous abrasion exists in 

 the same. When the urine is tinged with blood, w^e attri- 

 bute it to lesion of the minute vascular texture of the kid- 

 neys ; and that this does not more often happen is much 

 to be w^ondered at ; recollecting that these organs are situated 

 immediately within the sphere of action of the psoee muscles, 

 whose contractions, under heavy weights, must be con- 

 tinually exposing them to pressure. No observations will 

 be made on the components of sequine urine; but little 

 wonder will be felt on learning that the animal is occa- 

 sionally the subject of urinary calculi. 



THE MALE ORGANS OF GENERATION. 



The parts in the male are most of them external; on 

 the contrary, in the female, they are principally internal ; 

 but in both they are connected with the urinary organs, by 

 which one structure is made to answer two purposes. — 

 The scrotum, containing the testicles, is formed by the 

 integuments of the abdomen : outwardly it is smooth, thin, 

 and scantily supplied with hairs; it is next to the skin 

 enveloped by cellular substance, and then by a muscular 

 layer, called dartos, while its substance is divided by a 

 septum, marked by a raplie or external Hne of division 

 that completely separates the scrotal cavities. 



The testicles occupy the scrotum, and are two glan- 

 dular bodies, which are first formed within the abdomen. 

 Internally it is lined by a reflection of peritoneum derived 

 from the abdomen, and called the tunica vaginalis reflexa, 

 which as life progresses is drawn into the scrotum. The 

 coverings of the testicle are, first, a complete external one 

 of peritoneum, which is continued up the cord, and is 

 called the tunica vaginahs; then a partial one from the 



