INTERNAL SECRETION OF TESTICLE 129 



age, I even observed formation of spermatozoa. In mice, 

 Miss Kropman (1923) and I found full spermatogenesis in 

 the seminiferous tubules throughout both testicles seven weeks 

 after sectioning the vasa deferentia. By puncturing the 

 testicle Posner (1922) showed that as much as thirty years 

 after occlusion of the spermatic duct in gonorrhoeal epididy- 

 mitis spermatozoa may be present in the seminal tubules. 

 It may, therefore, be objected that the action of the gener- 

 ative part of the testicle was not wholly excluded in the 

 experiments of Bouin and Ancel. Tandler and Gross tried to 

 overcome this objection by experiments on roedeer. The 

 observation of the antlers of the roe is a good means of judging 

 whether the sexual gland was performing the internally secretory 

 function or not, because the antlers do not grow again in a 

 castrated animal ^ after being shed. In these experiments 

 Tandler and Gross found that in a roebuck whose vasa defer- 

 entia had been ligatured and cut, and whose seminiferous 

 tubules — as shown'by microscopical examination — had degene- 

 rated, the antlers grew again a year after the operation. 

 Retterer (1923) has, however, objected to Tandler and Gross 

 that the state of spermatogenesis in their operated roebuck 

 was like that in an animal just before puberty. 



The following objections to the conclusions of Bouin and 

 Ancel were recently made by Tiedje (1921). He ligatured 

 the vasa deferentia in adult guinea pigs and recorded some 

 weeks afterwards a decrease in sexual ardour; this decrease 

 lasted for some time, but subsequently the ardour increased 

 again. Tiedje explains these changes in the psycho-sexual 

 behaviour as due to changes in the seminiferous tubules; 

 degeneration of the generative tissue leads to a decrease, 

 regeneration to a restitution of the sexual ardour. My opinion 

 is that it is not possible to make statements about such rapid 

 changes in the psycho-sexual ardour of laboratory animals. 

 Even when castrated the animal shows for weeks and even 

 months no changes in sexual behaviour. Only morphological 

 changes can be taken into consideration as sure indications 

 of the state of the endocrine function of the sexual glands. 

 Although I saw about 40 animals on which I performed partial 

 castration (see below) with section of the ductus epididymidis, 

 I observed only once temporary morphological changes such as 

 Tiedje's theory would suggest. The horny styles in the blind 



