No. 627] GERM PLASM OF THE OSTRICH 316 



been domesticated it has never produced a feather varia- 

 tion, germinal in its origin, such as could he regarded as of 

 the nature of a sport or mutation. Feather irregularities 

 and abnormalities are by no means infrequent, but can 

 generally be ascribed to some injury to the feather germ 

 or follicle in the process of quilling, or to malnutrition. 

 Any peculiarity of this nature is usually forwarded to the 

 writer, and some of the more common irregularities have 

 already been described.^ They are never hereditary 

 peculiarities. 



This stability on the part of the various structural de- 

 tails of the feather has continued despite the great changes 

 to which the ostrich has been subject as a domesticated 

 creature. The birds are fed on the most nourishing and 

 stimulating of foods, the farmer having no option in the 

 matter if he is to secure a feather crop of the highest 

 quality; also they may be transferred from the moist 

 coastal planes to the dry and arid interior at an elevation 

 of 5,000 or 6,000 feet, a change involving great variation 

 in temperature, pressure and other conditions. As an 

 epidermal product, growing at the ra]Vid rate of a quarteV 

 of an incli daily, tlio fcntliiM- is cxti-iMiiol y sensitive to 

 changes in imlritioii niid cliinatic ('(.iiditions, often re- 

 sponding to tlio small dilTercticcs in hlood-pressure be- 

 tween day and night. Yet all tlu' iiioililications resulting 

 from these influences are somalic: no hereditary germinal 

 alteration has ever manifested it>elt'. 



Like so many other African animals, the giratfe, hippo, 

 rhino, elephant and ant-bear, the ostrich is a survival of 

 ancient days, a left-over, and as becomes a creature of 

 long ancestrj^ is fixed and immutable with regard to the 

 many characteristics of its plumage. Numerous germinal 

 changes have appeared in the past and survive to-day in 

 the various feather t^^^s recognized by the specialist, all 

 of wdiich breed true; but it can justly be claimed that no 

 further alteration has taken place during the past fifty 



