188 



THE KEPRODUCTIVE SYSTEM 



choudria) and fatty granules. The nature of the lipoid granules is dis- 

 cussed by White-head (Amer. Jour. Auat., 14, 1, 1912). These cells 

 increase in number during senile atrophy of the testis, but later entirely 



disappear. They are rela- 

 tively larger and more abun- 

 dant also in the testes of 

 tuberculous patients where 

 there is considerable degen- 

 eration and a general infan- 

 tile condition of the semi- 

 niferous epithelium. Vari- 

 ous functions have been 

 ascribed to them that is, 

 those obviously dependent 

 upon the internal secretion 

 of the testes prominently, 

 origin and maintenance of 

 secondary sexual characters, 

 and origin of sexual in- 

 stinct. Obviously other cells 

 of the testis might conceiv- 

 ably subserve these func- 

 tions, namely, the susten- 

 tacular cells and the sex- 

 cells. However, observa- 

 tions on testes of mules (in- 

 fertile) a n d cryptorchid 



FIG. 433. A GROUP OF INTERSTITIAL CELLS 

 FROM THE TESTIS OF A THIRTY-FIVE YEAR 

 OLD NEGRO. 



The outlines of three adjacent seminiferous 

 tubules are shown. Among the interstitial cells 

 are three nuclei of ordinary connective tissue. 

 The interstitial cells are filled with lipoid spher- 

 ules and granules. Formalin fixation, iron- 

 hematoxylin stain. X 1500. 



horses, and the findings of 

 Whitehead (Anat. Rec., 2, 

 5, 1908) in a third abdom- 

 inal testicle of a horse 

 where only interstitial cells 



in great abundance persisted in normal condition, would seem to rele- 

 gate these functions to the interstitial cells. 



Kiugsbury's careful studies (Amer. Jour. Anat., 16, 1914) of the inter- 

 stitial cells of the ovary of the cat (elements presumably homologous with 

 the interstitial cells of the testis) strongly support the interpretation of 

 these cells in terms of absorbers of degenerating and disintegrating ma- 

 terials. In the ovary all of the earliest and many of the later primary 

 oocytes disintegrate. In the vicinity of such atretic follicles interstitial 



