THE URINARY APPARATUS. 



157 



more than one calculus is present, and the smaller ones 

 and sabulous matter or gravel are passed periodically, and 

 Gowing records that in one of his cases the latter became 



Fig. 45. — Cystic calculus, after Moeton. 



deposited on the hair below the generative opening in a 

 bitch. The urine varies in colour ; sometimes it is red, 

 and distinctly contains blood, in other cases it is yellow 

 and thick from apparently pus, really urine crystals. 

 The smaller breeds of dogs are most liable to calculi in 

 the bladder, which are generally nucleated. Boerhaave 

 produced one by the artificial introduction of a small 

 rounded pebble, which acted as a centre of deposit in the 

 course of a few months. With the symptoms of chronic 

 cystitis we find in these cases a continuous flow of urine, 

 and resulting excoriation. The current is uncertain, and 



Fig. 46.— Cystic calculus, after Mobton. 



may be suddenly suppressed, and the animal show much 

 pain. In some cases there is detectable swelling in the 

 perinseum in the male. Mayhew considers as diagnostic 

 the animal finding a difficulty in going downstairs, having 



