Relation between the Thymus and the Generative Organs. 85 



Experiment 16. 



Initial weight. 



Final 

 weight. 



"Weight of i 

 testes. 



Initial 

 weight. 



Final 

 weight. 



Weight of 

 testes. 



Control Animals. 







Operated Animals. 



grm. 



grm. 



grm. 



grm. 



grm. 



grm. 



128 



258 



0-390 



132 



267 



-350 



150 



253 



0-520 



209 



267 



0-976 



129 



254 



0-510 



207 



264 



-330 



128 



255 



n •'71 



215 



255 



0-330 



160 



262 



0-520 



167 



255 



0-800 



135 



256 



0-580 



202 



259 



0-507 



219 



273 



0-580 



183 



• 255 



0-480 



236 



278 



0-740 









215 



279 



0-570 









Average 166 



263 



0-569 



187 



260 



0-539 



Experiment 17. 



Initial weight. 



Final weight. 



Weight of testes. 



Operated Animals. 





grm. 



grm. 



grm. 



198 



253 



-503 



172 



262 



0-790 



152 



255 



0-465 





253 



0-680 



174 



256 



0-609 



Summary of Conclusions. 



From the evidence given in the above set of experiments, where, in 

 investigating growth effects, the authors were careful to compensate for any 

 possible operative effects, are drawn the following conclusions : — 



(1) Eemoval of the thymus in young guinea-pigs does not affect the 

 growth of the animals. 



(2) Eemoval of the testes and epididymes in young guinea-pigs does not 

 affect the growth of the animals before sexual maturity. 



(3) Simultaneous removal of the testes and thymus in young guinea-pigs 

 does not affect the growth of the animals before sexual maturity. 



(4) Thymectomy is not followed by hypertrophy of the testes. 



(5) Castration leads to an arrested atrophy and subsequent hypertrophy of 

 the thymus gland, as found by other investigators. 



