PELICAN ISLAND 207 
ground or in the trees respectively Or, assuming 
that the same individuals might build a stick nest 
in the bushes one year and a straw nest on the 
ground the next, we have an unusual variation in 
the character of the nest of the same species. In 
the case of the Fish Hawks of Plumb Island the 
birds evinced an appreciation of the protection 
afforded them by the owner of the island by often 
placing their nests on the ground. Photographs 
of these nests, however, made by Dr. C. 8. Allen, 
show that the birds employed as much material 
when nesting on the ground as when nesting in 
trees, the eggs on the ground being surrounded by 
a useless mass of large sticks. Certain of the 
birds, therefore, in response to new conditions, had 
chosen new nesting sites, but had not as yet made 
corresponding changes in the character of their 
nests. 
When the nest is completed, as we have seen, 
from one to three eggs are laid. The period of incu- 
bation is probably about four weeks, and a careful 
listener may detect the presence of a hatching egg 
by the choking bark which the young Pelican begins 
to utter as soon as he has made an opening in the 
shell which holds him. When he has finally freed 
himself and appears in the world, he is about as 
unattractive a bit of bird life as can well be con- 
ceived.’ His dark, purple skin is perfectly naked, 
he is blind, and when he is deprived of shade pro- 
vided by the brooding parent, he twists restlessly 
about in the nest, uttering the same choking bark 
with which he first greeted the light. 
Even at this early age he displays one of the 
