The Eggs of Birds 441 



Arctic-breeding owls, where the nesting must take place at 

 an unreasonably early and cold date in ordcj- to gi\(' (he 

 fledglings time to reach ntature strength hefore llie suc- 

 ceeding winter assails them, is that these birds deposit 

 their eggs at intei'xals of a week or ten da\s. Iti I his 

 way the mother can envelop in her plumage and keep 

 thorough!}' warm one egg and a callow fledgling at a 



Fig. 350. — Eggs of Screech Owl. 



time, and is assisted, in respect to the later eggs and 

 fledglings, by the warmth of the oldei- young in the nest. 

 "The parrots are a wide-spread and numerous ti'ihe, 

 and none of the larger species need lay more than two 

 or three eggs, for they protect them in deej) holes in the 

 earth or in trees, and are able to defend them; but some 

 of the smaller parrakeets lay as many as twehe eggs, 

 reflecting the greater dangers with which the}' have to 



