358 INTERNAL SECRETIONS 



birds were killed after sexual maturity was attained, and in 

 seven cases ovarian tissue could not be detected. AU the birds 

 showed normal somatic and psychical masculinity, even those 

 birds in which ovarian tissue was found. Zawadowsky 

 (1922) implanted one testicle into the normal hen. Six experi- 

 ments of this kind were made. In one case the graft persisted 

 for a longer time. There was no decided influence of the 

 testicular graft on the ovary, and vice versa, as the hen showed 

 all the female sex characters and even laid eggs at a time when 

 the comb had already begun to hypertrophy. Further, 

 Zawadowsky engrafted ovaries into normal cocks; five experi- 

 ments of this kind were made. In one case the graft took 

 and exhibited its influence on the sex characters. There was 

 also a decided antagonism of the sex glands in the experiments 

 of Minoura (see p. 311). This antagonism does not, however, 

 exclude the possibihty of experimental hermaphroditism in the 

 fowl as shown by the above-mentioned experiments of Zawa- 

 dowsky and by those of Pezard, Sand and Caridroit (see p. 410), 

 all depending, as I think, upon the quantities and the condition 

 of testicle and ovary simultaneously present. 



It is of great interest to note that in Arthropoda, where 

 there is no hormonic activity of the sex gland, the gonad 

 develops normally in every respect when engrafted into an 

 animal of another sex which has been unilaterally castrated. 



New experiments of Matsuyama (1921) should also be 

 referred to here. Matsuyama made observations on rats 

 in parabiosis, uniting normal and castrated males with 

 normal and castrated females. He found that the testicle 

 of a male united with a normal female several months 

 afterwards undergoes degenerative changes like those after 

 ligation of the vas deferens, transplantation, irradiation and 

 so on; the ovary undergoes changes which seem to me to be 

 similar to those after transplantation or irradiation. At first 

 thought one might be disposed to consider these results as 

 caused by an antagonism between the gonads of different 

 sexes. Now, it is of great interest that- similar degenerative 

 changes in the testicle occur also if the normal male or female 

 has been united with a castrated partner of the opposite sex. 

 There never was feminization or masculinization of the 

 castrated partner. Evidently here certain factors are involved 

 which are beyond our actual knowledge. As far as I can see from 



