T. H. MORGAN 



Breast 



Feathers from hen-feathered male Sebright (J, 2, 3, 4) that changed to cock- 

 feathered male (l a , 2 a , 3 a , 4 a ) after castration; and then began to go back as the 

 testes regenerated (l b , 2 h , 3 b , 4M ; then changed again to cock-feathering after 

 castration (lc, 2 C , 3 e , 4 C ) 



