RESULTS OF CASTRATION IN DUCKS. 



45 



given their liberty out of doors. This procedure at once revealed 

 that two individuals carried sex feathers. As no males were 

 with the flock, they were immediately examined carefully. Their 

 band numbers, of course, provided the necessary identification. 

 No. 4 (Fig. 9) in addition to the sex feathers, had breast feathers 

 similar to those of the male's breast in summer plumage. In a 

 few feathers, gray vermiculations were present. Such other 



FIG. 10. Female 24, castrated. Photographed August. 



modification as had taken place (e. g., very little buff in dorsal 

 regions) was not beyond the range of variation in normal females. 

 No. 24, Fig. 10, was rather more strongly modified. She had a 

 very narrow white neck ring. The feathers of the breast were 

 distinctly of the male type (Fig. 4, /, J). Those of the dorsal 

 side of the lower neck region were of a type occasionally occurring 

 in the same region in males. In other parts of the body there 

 was a distinct tendency for the buff bands to become transverse. 

 Compare Fig. 6, G, H. Feathers, more or less vermiculated, 

 were quite common. A few found in the anal region, were in- 

 distinguishable from similar male feathers. Compare Fig. 8, G 

 with /. 



