DUCTLESS GLANDS. 34:9 



functions. The voracity which occasionally follows the op- 

 eration in animals is one of the phenomena, like the increase 

 in the size of animals after castration, for which physiologists 

 can offer no satisfactory explanation. 



It is evident from the foregoing considerations that, not- 

 withstanding the great amount of literature on the anatomy 

 and functions of the spleen, physiologists have no definite 

 knowledge of any important office performed by this organ. 

 With this conclusion, we pass to a consideration of the other 

 ductless glands, the physiology of which is, unfortunately, 

 even more unsatisfactory. 



Suprarenal Capsules. 



The theories that have been advanced with regard to the 

 function of the suprarenal capsules have not, as a rule, been 

 based upon anatomical investigations, but have taken their 

 origin from pathological observations and experiments on 

 living animals. This fact detracts from the physiological 

 interest attached to the structure of these bodies, and we 

 shall consequently treat of their anatomy very briefly. 



The suprarenal capsules, as their name implies, are situ- 

 ated above the kidneys. They are small, triangular, flat- 

 tened bodies, placed behind the peritoneum, and capping the 

 kidneys at the anterior portion of their superior ends. The 

 left capsule is a little larger than the right, and is rather 

 semilunar in ^ form, the right being more nearly triangular. 

 Their size and weight are very variable in different individ- 

 uals. Of the different estimates given by anatomists, we 

 may state, as an average, that each capsule weighs about 

 one hundred grains. They are about an inch and a half 

 in length, a little less in width, and a little less than one- 

 fourth of an inch in thickness. 



The weight of the capsules, in proportion to that of the 

 kidneys, presents great variations at different periods of life ; 

 and they are so much larger in the foetus than after birth, 

 that some physiologists, in default of any reasonable theory 



