THE OEGANS OF REPRODUCTION 91 



causing the sexual elements to disappear; yet the 

 interstitial cells not only are left, but actually in- 

 crease in number. And what is far more remark- 

 able, the sexual instincts remain as strong as ever. 

 This is therefore further evidence in favor of the 

 view that puberty is dependent not upon the pres- 

 ence of the reproductive elements, but rather upon 

 the production of an internal secretion due to in- 

 terstitial cells. 



Brown-Sequard. In 1889 Brown-Sequard, one- 

 time professor at Harvard, and later professor at 

 the College de France in Paris, presented a paper 

 before the Academic de Medecine that created a 

 sensation. He described experiments in which he 

 had himself injected with extracts obtained from 

 the sexual organs of a ram; the result was that he 

 had become quite "rejuvenated." Despite his 

 seventy years he felt, he said, like a youth, with 

 all a youth's vigor. The newspapers, quite justi- 

 fiably, gave much prominence to this get-young- 

 quick method, and for a short time Brown-Sequard 

 was an international hero. Then came cries from 

 opposition forces. The experiments were repeated 

 and nothing like what was alleged by the French- 

 American could be discovered. Brown-Sequard 

 answered his critics by charging that his technique 

 had not been followed with sufficient care. But 

 his replies did not satisfy the critics ; they attacked 

 him mercilessly, and continued the attack until the 



