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BENJAMIN HORNING AND HARRY DEAL TORREY. 



A Rose Comb Brown Leghorn female, hatched April 9, 1923. 

 was ovariotomized May 6, 1923. Thyroid feeding was begun at 

 once. Fig. 4 is a photograph of this bird almost two years 



FIG. 6. Representative saddle feathers from three adult B. L. females which 

 are, from left to right; the bird shown in Fig. 4, a normal thyroid fed female, and 

 a control. 



later, just before she was killed on March 28, 1925. The comb 

 and wattles are large and well formed. The spurs are 2 cm. long. 

 Sickles are present among the feathers of the tail. These are all 

 male characters, assumed as a consequence of ovariotomy. The 

 body conformation is of the female type, as is, in general, the 

 plumage. One exception to this statement has already been 

 noted, namely, the presence of tail sickles. Another is to be 

 found in the neck hackles which, though not well shown in the 

 photograph, approximate in form and structure and color the 

 hackles of thyroid fed male birds. In general, the plumage is 

 duskier than in unaltered females. This is especially true for 

 hackles and saddles. The former may have no lacing, or they 

 may be laced intermittently in the fashion characteristic of 

 thyroid fed males. In neither case, however, do traces of the 

 mottling remain that is so conspicuous in the female hackle. 

 The saddles, which are female in form and structure, show 

 traces of mottling but along with the hackles show an intensity 

 of melanin pigmentation that surpasses the results, mentioned 

 above, on unaltered thyroid fed females. 



