FEATHER INDUSTRIES 179 



and deposit their eggs there. As fast as the eggs 

 arrive they are removed from the nest, a proceed- 

 ing which causes the bird to lay steadily until 

 perhaps fifty, sixty, or even one hundred eggs 

 have been produced, instead of the normal baker's 

 dozen. The eggs are then enclosed in specially 

 constructed incubators and maintained at a tem- 

 perature of 99 to 100° P, for a period extending 

 over forty-two days. 



The chicks are already the size of ordinary do- 

 mestic fowls when they emerge from their thick 

 shells ; their grayish bodies are mottled with dark 

 spots. Growth is rapid, — ^nearly one foot in 

 height a month, — and when adult size is reached 

 their heads will rear seven or eight feet from the 

 ground. By that time they weigh three or four 

 hundred pounds. At four years of age they com- 

 mence to breed. 



Commercial ostrich-plumes are those feathers 

 which sprout from the tail and the misshapen 

 wings. Each wing produces forty-two major 

 quills, a number which is never exceeded, though 

 many attempts have been made to increase it by 

 artificial selection. Plucking commences when the 

 birds are six months old. The feathers then are 

 of an inferior quality, small, and termed "spa- 

 donas" from their spear shape. It is the prac- 

 tice in South Africa to clip the birds every six 

 months thereafter, both sexes producing plumes. 



At plucking time the ostrich is driven into a 



