186 THE SHEPHERD'S HAKUAL. 



sheep is not so copious as that of the cow in proportion to its size, 

 but possesses a larger proportion of salts. The following is an 

 analysis of sheep's urine : 



Water 96.0 per cent. 



Urea with some albuminoids and coloring matter 2.8 " " 

 Salts of potash, soda, lime, magnesia, silica, iron, 

 alumina, and manganese T . . 1.2 " " 



100.00 " 



In fig. 73 is shown a section of the substance of the kidney 

 highly magnified, in which appear the uriniferous, (urine carrying) 

 ducts or tubes, (a, a), surrounded by the secreting glandular sub- 

 stance, (&, &), which is enclosed in the net-work of the arteries, 

 (c, c), and the fibrous tissue, (tf, d). 



The bladder is situated hi the pelvic cavity, or the lower part of 

 the abdomen. It is composed of two coats, the outer one being 

 muscular, and capable of contracting so as to expel its contents. 

 One half is enveloped in a third coat, and the other half in the 

 /, tissue of the pelvic 



. n '- 



region, and masses of 

 fatty matter. The mus- 

 cular coat consists of 

 fibers Placed in various 

 directions, lengthwise, 

 crosswise, oblique, and 

 spiral, so that in the act 

 of contraction the blad- 

 der is reduced in size 

 Fig. 73. STBUCTUBB OF THE KIDNEY. eve nly and in every 



direction. A strong muscle encircles the opening, from which the 

 urine is discharged, and which is called the neck of the bladder. The 

 contraction of this muscle closes the neck and retains the contents, 

 its relaxation opens the orifice and Callows the contents to be ex- 

 pelled. From the neck of the bladder proceeds the urethra, by 

 which the urine is discharged. In the ewe the urethra is very 

 short, in the ram it is much longer, and passes down from the 

 anus along the abdomen to the extremity of the penis. The func- 

 tions of the bladder are very important. It serves as a reservoir 

 for the urinal fluid which is constantly secreted by the kidneys 

 and retains it until a considerable quantity has been accumulated, 

 and thus spares the animal from otherwise continually dribbling 

 away the urine as it is secreted. 



The Eeproductive Organs. These are entirely different in the 



