STUDIES ON THE DURATION OF LIFE 219 



The presumption that Steinach's experiments have 

 really brought about a statistically significant lengthen- 

 ing of life is large, and the basis of ascertained fact 

 small. After a careful examination of Steinach's bril- 

 liant contribution, one is compelled to take the view that, 

 however interesting the results may be from the stand- 

 point of functional rejuvenation in the sexual sphere, 

 the case is not proven that any really significant length- 

 ening of the life span has occurred. In order to prove 

 such a lengthening we must, first of all, have abundant and 

 accurate quantitative data as to the normal variation of 

 normal rats in respect of duration of life, and then show, 

 having regard to the probable errors involved, that the 

 mean duration of life after the operation has been signi- 

 ficantly lengthened. This Steinach does not do. His 

 paper is singularly bare of statistical data, We may well 

 await adequate quantitative evidence before attempting 

 any general interpretation of his results. 



Indeed, one may note in passing that the case does 

 not seem entirely clear in respect of Steinach's results 

 in the purely sexual sphere. Thus Romeis has repeated 

 the experiments, and finds, from comparative histologi- 

 cal studies on the genital organs of rats, before and after 

 Steinach's operation, that there is no evidence of any 

 increase in Ley dig's interstitial cells, and hence none 

 of the so-called ' ' interstitial or puberty gland. ' Romeis 

 noted no increase in sexual desire among his rats after 

 the operation. The hypertrophy of the seminal vesicles 

 and prostate, described by Steinach f ollowing the opera- 

 tion, was also seen by Romeis, but found, by the latter, to 

 be merely the result of the stasis of the secretions nec- 

 essarily consequent upon the operation, and not a true 

 functional hypertrophy at all. 



