SEXUAL CHARACTERS OF SOME DOMESTIC BIRDS. 25 



slowly, probably accompanied by the development of the "Wolffian 

 body" pari passu. A further discussion can best await the results of 

 the examination of several other instances *of similar nature now on 

 hand. 



No. 2058. This bird is of considerable interest. She is a pure-bred 

 Brown Leghorn from the stock of one of the best-known breeders of 

 the variety in this country. She was 2 months of age when the 

 ovary was removed. In 2 weeks the first male feathers had begun to 

 appear. The development of male characters continued until late in the 

 fall, when she was a very good young male in appearance. As stated 

 above, young males and castrated females under some circumstances 

 are slow in reaching a complete development of the adult plumage. 



In this instance, the bright feathers of the wing bow were relatively 

 few in number, while the hackle, back, and saddle feathers, though of 

 adult color and shape, were quite short. While she was confined during 

 the winter, most of the saddle feathers were picked off by her mates. 

 The new feathers that came in were short, rounded at the end, and with- 

 out barbuleless barbs ; the ground color was black, the distal portion of 

 the shaft often red, and the web sometimes sprinkled with minute brown 

 spots. As somewhat similar feathers may often be seen in young males, 

 Httle attention was paid to the matter until late in the summer of 1914, 

 when it was observed that the bird was not developing the expected 

 adult male coat of feathers. The shape and size of the feathers of the 

 new coat are more like those of a hen-feathered male, while the color 

 of the feathers of the back, saddle, and wing bow remained essentially 

 as described. The rest of the bird is colored like a male. This bird 

 has a well-developed comb, wattles, and spurs, and in a sense corre- 

 sponds to the Type II of the ducks. By means of an operation it has 

 been determined that no ovary was present. 



Female Fowl Partially Ovariotomizbd. 



In several instances the ovary has not been entirely removed; indeed, 

 in some instances, only a small fraction was taken out. In such cases 

 no changes followed the operation. From other individuals almost 

 all the ovary was removed, so much so that male plumage was devel- 

 oped in varying degrees, though no definite relation between the amount 

 of ovary removed and the degree to which the secondary sexual char- 

 acters of the male developed has been made out, because the exact 

 amount of ovary left has not been known, though in a few instances 

 none could be seen with the naked eye. 



An interesting example of incomplete removal is afforded by No. 

 4140. This individual was a hybrid female, whose original band had 

 become lost. She was about 3 months old at time of operation and 

 had well-developed female plumage. The removal, according to the 

 protocol, was probably complete, though it was possible that a httle 



