X11 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 
