128 
BIRDS OF PENNSYLVANIA. 
like all other rapacious birds, will defend itself with its claws and bill 
against all advances. A stick or gun barrel presented to it, when crip- 
pled, will be grasped, and the bird can be carried pendant from the same 
a considerable distance before it will loose its hold. With such tenacity 
do they hold on that a friend of mine who had winged one, in his en- 
deavors to capture it alive, had the bird to fasten on his forearm with 
both claws ; to relieve himself he was obliged to take out his penknife 
and sever the tendons of both legs. 
Nest building generally occurs in March and lasts from eight to 
fifteen days. The nest is built in the woods, commonly on a large oak 
or hickory tree. A pair of these hawks resorted for five consecutive 
years to a large oak tree {Quercus tinctoria), for nesting purposes, in a 
belt of timber adjacent to the far-famed Deborah's Rock, East Bradford 
township. The nest a rather bulky structure, is made, externally, of 
sticks and twigs, some of the former being an inch in thickness ; inter- 
nally, it is lined with leaves and the inner layer of bark — usually from 
the oak and chestnut trees. This lining of bark is frequently torn in 
shreds. 
Certain ornithologists, Audubon among the number, have found five 
eggs in their nests. I have, however, mostly found two, and on no 
occasion have I found more than three to constitute the full complement. 
The eggs, about 2.40 by 1.85 inches, vary much in their markings. Their 
ground color is a dull white or rusty white, marked with minute brown 
spots, or with large purplish dark-brown blotches, often covering the 
greater part of the egg. Incubation lasts about three weeks. Certain 
writers claim that this species will boldly defend invasion of its home 
on the part of man. Such may have been the experience of others, but 
such statement is the reverse of my experience. I have taken both eggs 
and young, and, as yet, I have encountered no opposition; but have 
found them cowardly, flying away, in fact, beyond gunshot at my ap- 
proach, uttering cries of distress, and seemingly to engage in mutual 
condolence over their misfortune. 
During the breeding season they frequently hunt together for food for 
themselves and young, and if, perchance, they spy a squirrel on a tree, 
one will drive it while the other poises itself ready to seize it if it dodges 
to the other side to evade the grasp of the first hawk. From the two 
there is no escape. Grasping it firmly by the neck, the assailant prac- 
tically demonstrates the possibility of garroting its victim, when the ill- 
fated squirrel is carried to the eyry and torn to pieces to satiate the 
cravings of their rapacious young.” — Wood. In consequence of limited 
space it is impracticable to give in detail the results of dissections which 
I have made of this species, but would state briefly that my examina- 
tions of one hundred and seventy -three Red-tails captured in Pennsyl- 
vania, chiefly in Chester county, revealed in one hundred and twenty- 
