A CASE OF TRUE HERMAPHRODITISM IN THE FOWL 195 

 SUMMARY 



1. There is described in this paper a Rhode Island Red fowl, 

 nine years of age, which possessed an ovotestis and a testis, 

 both active. The hermaphrodite displayed external charac- 

 ters and behavior of both sexes. 



2. Other similar cases previously described in the literature are 

 summarized in table 1 and reviewed. 



3. The ovotestis contains both the 'interstitial' cells of Boring 

 and Pearl and the 'luteal' cells of various authors. The former 

 are regarded as the basophilic stage in the life-history of eosino- 

 philic leucocytes. The latter are probably the endocrine cells of 

 the ovary responsible for hen-feathering. 



4. Although we are in almost total ignorance concerning the 

 endocrine cells of the testis, yet the fact appears to be established 

 that this organ does secrete a hormone which influences the 

 behavior and certain secondary sex characters, notably the comb 

 and wattles. The evidence, including that furnished by the 

 hermaphrodites, is reviewed. 



5. Experiments are suggested which might be expected to 

 clear up some of the mooted and obscure points in this field. 



6. Genetic and cytological data must supplement physiological 

 facts in the elucidation of secondary sex characters in fowl. 

 In the writers' opinion, a mere beginning has been made towards 

 this end. 



