930 R. G. HOSKINS 



were widely accepted as valid. His findings have been confirmed by 

 Tandler and Grosz (a), by Soli, by Cimorini, and by Schutz (cited by 

 Gushing, 1910) on animals, and somewhat doubtfully by Kon (1909) in a 

 study of the hypophyses of 7 women and 1 man after surgical castra- 

 tion. Marrassini and Luciani (1911) reported a somewhat elaborate 

 study of the problem. Their observations were made on sheep, cattle, 

 dogs, rabbits, guinea-pigs, and domestic fowls. They were unable to de- 

 tect any significant difference between the hypophyses of the normal and 

 the control animals. Similar negative results were reported by Livingston 

 (c) (1916). Rabbits served as experimental animals. From an extensive 

 body of data he reached the conclusion that neither males nor females 

 show a constant hypertrophy of the hypophysis following extirpation of 

 the gonads. Massaglia (1920) found in 4 capons hypophyses approxi- 

 mately twice as large as those of 7 normal control cocks. 



The weight of the available evidence indicates that castration results 

 in some degree of hypertrophy of the hypophysis. There is some evidence 

 that the eosinophilic cells are especially affected. The problem., however, 

 cannot be regarded in any way as settled. 



Relation between Thymus and Gonads. In view of the fact that 

 a certain degree of involution of the thymus gland occurs at about the time 

 of puberty, a theory has gained considerable credence that an important 

 relationship subsists between this organ and the gonads. Apparently the 

 first to investigate the matter experimentally was Calzolari (1898). In 

 each of 6. rabbits previously castrated he found the thymus was larger 

 than in normal animals. Henderson (1904) compared the weight of the 

 thymus gland in 100 castrated male cattle with the normal weight for 

 this species, and found evidence of persistence of the thymus. Similar- 

 observations were made in guinea-pigs and rabbits. Henderson stated 

 also that in cattle of both sexes that had exercised the reproductive func- 

 tion, thymus involution was accelerated. Goodall (1905) made a histo- 

 logical study of the thymus glands of guinea-pigs previously castrated and 

 noted that both the lymphoid tissue and the corpuscles of Hassall shared 

 in the delayed atrophy which he regarded as characteristic. Soli, in 10 

 rabbits and 15 capons, noted thymus persistence after castration, and 

 Tandler and Grosz made similar observations in roebucks, dogs, and goats. 

 All such observations are subject to the general criticism that castration 

 tends to result in overgrowth or a high state of nutrition in various tissues. 

 It is quite probable, therefore, that these observers have noted merely 

 the converse of the thymus wasting which occurs in inanition or emaciation 

 from any cause. 



Several observers have studied the effects of thymectorny on the sex 

 glands. Paton (a) (b) (1904, 1911) reported that this operation causes a 

 more rapid growth of the testes than normal. Soli, however, reported pre- 

 cisely the opposite effect. Bracci (1905) was able to detect no gross 



