378 CARL R. MOORE 



now of large size, were recovered, preserved, and sectioned for 

 study. Animal 68 Bl was killed February 15, 1919, seven 

 months after the original transplantation, and the two grafts 

 likewise recovered, preserved, and sectioned. 



The psychical reactions of each of these animals had been those 

 of a typical male for some months before they were killed. Upon 

 introduction of a strange animal into the cage of either of the 

 two, the animal became very excited and began to emit the char- 

 acteristic call of the male animal as it approached the strange 

 one. If the latter animal was a female the psychically changed 

 female attempted to imitate the copulatory reactions of the nor- 

 mal male animal, while if the animal introduced was a male a 

 fight usually began. In the male-like reactions each of the two 

 animals were decidedly vigorous, and one observing their behav- 

 ior would conclude at once that the animal was a normal male. 



The somatic characters that distinguish a male guinea-pig from 

 a female are indeed few, but the configuration of the external geni- 

 tals is one distinct feature that serves as a ready means of iden- 

 tification of the two sexes. And inasmuch as the development or 

 differentiation of the external genitals are not entirely completed 

 fifteen days after birth, they would be subject to influences of the 

 implanted sex gland. 



In each of the two individuals decided modification of the con- 

 figuration of the external genitals occurred. The clitoris of the 

 female underwent considerable hypertrophy, producing a promi- 

 nence that externally resembled very decidedly the male penis. 

 As a result of this the general configuration of the genital region 

 resembled the male condition considerably more than the female. 



Lipschiitz, observing one of Steinach's transformed females, 

 has written several papers describing the modification, and inas- 

 much as the transformation in the animals of my series differs 

 in no material respects from that described by Lipschiitz, further 

 description of the conditions will be omitted. 



Observations on the two female guinea-pigs of my series con- 

 firms the findings of Steinach that testis grafts will persist and 

 grow in the female, and that associated with this growth 

 the female may develop a typical male behavior toward both 



