570 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1910. 



ferent appearance from the rest of the body (pi. 3, fig. 2; pi. 4, fig. 1). 

 Examples of the neck and head feathers as they occur in the adult 

 ostrich are shown in plate 8, figure 1. In most cock birds a con- 

 spicuous ring of small white feathers occurs toward the base of the 

 neck; that is, where the black body feathers pass into the gray neck 

 feathers (see the cock in pi. 4, fig. 1). Two of these are shown in 

 plate 8, figure 1, and reveal that a few of the barbs at the tip are 

 prolonged beyond the others in a hairlike fashion. This character 

 becomes more emphasized in the feathers covering the rest of the neck 

 and head, as shown in the same illustration. They are downlike in 

 character, the quill and shaft undeveloped, the barbs delicate and 

 hairlike, and the central barb prolonged much beyond the others. 

 Owing to these long barbs the neck and head seem as if provided 

 with a sparse covering of hair, which is especially concentrated as a 

 circular tuft around the ear openings and also around the eyelids, 

 forming the eyelashes. 



The under or ventral body feathers are small and black in the cock 

 but white or gray in the hen. In the adult the feathers have all or 

 nearly all disappeared from the upper part of the leg, which is then 

 naked throughout its length; the original feather sockets show, how- 

 ever, for a long time. 



The third and fourth clippings are generally considered to repre- 

 sent the best efforts of the ostrich in the direction of feather produc- 

 tion (pi. 8, fig. 2). The plumes do not improve from this time 

 onward, so that the farmer is now fully aware of the feather value 

 of his bird. Ostriches which are well treated continue to produce 

 feathers of the same quality for a number of vears, well authenticated 

 cases being known of birds 35 to 40 years old which still produce a 

 good plumage. Where, however, the production is forced, as in 

 securing a clipping every eight or nine months, some birds are found 

 to deteriorate after four or five years; but great variation is observed 

 in this respect. The plumes also depreciate rapidly if the practice 

 is followed of drawing the feathers or quills before they are fully 

 ripe. A bird almost useless for feather production may yet be valu- 

 able for breeding. 



A few general considerations call for notice. The approximate 

 ages given above at which the wing plumes attain ripeness only apply 

 to ostriches under domestication, in which evenness and greater 

 frequency of growth is attained by pulling the quills immediately on 

 attaining ripeness. By this means clippings are secured at 6 months, 

 at 14 months, and at about 2 years, the last representing the adult 

 plumage. When left to themselves; that is, when not drawn arti- 

 ficially, the quills are not all molted at the same time; some will 

 remain in their sockets for months longer than others and hence 



