INTERNAL SECRETION OF TESTICLE 



189 



the Urodele testis. He stated that hpoid inclusions appear in 

 the interstitial cells only after the spermatozoa have left the 

 testicle; after the degeneration of the seminiferous part the 

 interstitial cells disappear. Like Champy, Humphrey con- 

 cluded that the interstitial cells in the Urodele testis have 

 no bearing either on the spermatogenesis or on the nuptial 

 changes. Perez considers the interstitial cells of the triton as 

 phagocytes without any relation to the internal secretion. 



A statement which is in complete contradiction to that of 

 Champy and Humphrey was lately made by Aron (1921), a 



Fig. 93. — Diagram : Cyclic development of generative and 

 interstitial tissue of the testicle of amphibians. — Plain 

 lines indicate generative tissue; dotted lines interstitial 

 tissue. Parallelism in Rana fusca and viridis, in Hyla 

 arborea and Bufo vulgaris. No parallelism in Rana 

 esculenta (as in the mole, see Fig. 91.) — From 

 Rasmussen. 



pupil of Bouin, on another triton, Molge cristata. Here the 

 male assumes in spring a nuptial apparel, consisting of a comb 

 on the back, and other characteristics concerning the colouring 

 of the skin ; the nuptial characters disappear in May or June. 

 No interstitial cells of a glandular nature are to be found 

 in the testicle. But at the time of heat there is near the hilus 

 of the testicle a tissue with rich fatty inclusions, which can be 

 easily recognised by its reddish-yellow colour.^ This tissue 

 is formed of spermatic cysts in which the cells of Sertoli had 

 undergone a peculiar transformation. These cells proliferate, 



^I am indebted to Dr. Wagner for having demonstrated this fatty body 

 to me both in situ and microscopically. 



