xii INTRODUCTORY 



It has been a difficult matter to collect facts for the 

 breeding range and season because there is no pub- 

 lished data on the subject; but the work has been 

 conscientiously done, and every precaution taken to 

 prevent possible errors. The dates given include the 

 earliest and latest at which eggs or newly hatched 

 young are usually found. It will be seen from this 

 that especial attention has been given to the habits of 

 each species during the reproduction period, including 

 nest-building, incubation, care of the young, etc., all of 

 which, unless otherwise accredited, has been taken 

 from the author's own notes. 



Long and careful study of the feeding habits of 

 young birds in California and the Eastern United 

 States has led the author to make some statements 

 which may incur the criticism of ornithologists who 

 have not given especial attention to the subject. For 

 instance, — that the young of all macrochires, wood- 

 peckers, perching birds, cuckoos, kingfishers, most 

 birds of prey, and many seabirds are fed by regurgita- 

 tion from the time of hatching through a period varying 

 in extent from three days to four weeks, according to the 

 species. Furthermore, that birds eating animal flesh 

 or large insects give fresh (unregurgitated) food to 

 their young at a correspondingly earlier stage of devel- 

 opment than do those varieties which subsist on small 

 insects or seeds. Also, that exclusive seed eaters are 

 usually fed by regurgitation so long as they remain in 



