128 INTERNAL SECRETIONS 



vasa deferentia have been ligatured, and in whose testicles the 

 seminiferous tubules underwent degeneration, one must 

 conclude that a normally developed generative tissue is not 

 necessary for the performance of the endocrine function of the 

 testicle. The experiments of Ancel and Bouin were repeated 

 with other animals: by Tandler and Gross (1913) on roe- 

 deer, by Steinach (1912) and Myers (1915) on rats, by Sand 

 (1918) on rats, rabbits and guinea pigs, by Berhlinger (1921) 



:/ 



^ & ^ ^ " »r ■"" 



%^^^ V- ^ ^•. *•.. ,, i^ 



/ 





.'rl 



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Fig. 61. — Section through testicle of guinea pig 78 days after liga- 

 ture of vas deferens, x 400. No spermatogenesis ; seemingly 

 only cells of Sertoli present. Interstitial cells well 

 developed. — From Ancel and Bouin. 



on guinea pigs, and by Kuntz (1921) on rabbits and dogs. These 

 investigations have confirmed the statements of Ancel and 

 Bouin. 



The degeneration of the seminiferous tubules takes place a 

 considerable time after the ligature is made, and it seems that 

 several months later a regeneration of seminiferous tubules 

 may occur. This was shown to be probable by Steinach 

 (1920), and confirmed by Tiedje (1921) on guinea pigs, whereas 

 there seems to be no regeneration in the rabbit. According to 

 Sand (1918) spermatogenesis in young animals (guinea pigs 

 and rats) is not completely stopped by hgature of the vasa 

 deferentia. In guinea pigs, in which I sectioned the ductus 

 epididymidis for other experimental purposes at a very early 



