BurNS—On BroAD-WINGED HAWK. 26 
~z 
of four taken May 27, '05, incubation varied from fresh to 
above one week in one egg. Other sets, however, exhibited 
uniform incubation, which is the rule. Walter A. Angell took 
an egg and two young just hatched, from a nest on June 19, 
1907, and the egg hatched under a hen the next day. 
Bendire places the period of incubation at from 21 to 25 
days. Near Berwyn, on May 19, ’01, at 12 M., I flushed a fe- 
male from the same nest as that used in 94. Two large eggs 
lay on a bed of chestnut bark scales, and a single ‘bunch of 
green chestnut-oak leaves, just garnered. Bird not on at 5:14 
P. M. On May 30, I found the lightest marked egg standing 
on its greater end, punctured by a nest twig. It contained a 
rather medium-sized embryo. The bird was not seen, though 
the sound egg was warm. May 31 the male was flushed, no 
additional lining except a single moulted secondary. June 10, 
at 7 P. M., flemale flushed: sides of nest built up neatly, fence- 
like and about three inches all around with green chestnut-oak 
leaves and several clusters placed under the egg, the latter 
slightly cracked at one side. Female protested at the slowness 
of my decent. June 12, 7 P. M., parent stole off silently and 
unseen. I heard the faint peeping of the nestling before I was 
within ten feet of the nest. It had just hatched and not yet 
entirely free from the large end of the shell, sprawling upon its 
breast with chin resting on the side of the nest' The female 
uttered a protest from a nearby tree, and I hurried down, be- 
ing just seven minutes from time of strapping on climbers un- 
til on my road home. I would place the period of incubation of 
this egg at fully 24 days, as to the best of my knowledge the 
egg was perfectly fresh on the 19th of May. I regret to say 
that all other of the several tests made by me, were less per- 
fect through my inability to ascertain the exact dates of com- 
mencement, though I have been fortunate enough to be pres- 
ent within an hour of the hatching on more than one occasion. 
Fred H. Carpenter offers two instances for calculation, both 
from Bristol Co., Mass.; May 17, 03, two eggs; June 4, no 
change; June 12, one young at least two days old, and one ad- 
dled ege. May 17, ’03, three eggs, one taken proved fresh; 
