214 
ICTERUS PECORIS. 
up the sides of the nest. Five days after the discovery, 
I perceived the shell of the finch’s egg broken, and the 
next the bird was hatched. The sparrow returned 
while I was near the nest, with her mouth full of food, 
with which she fed the young cow bird, with every 
possible mark of affection, and discovered the usual 
concern at my approach. On the succeeding day only 
two of the sparrow’s eggs remained, and the next day 
there were none. I sought in vain for them on the 
ground, and in every direction. 
“ Having found the eggs of the cow bird in the nest 
of a yellow-throat, I repeated my observations. The 
process of incubation had commenced, and, on the 
seventh day from the discovery, I found a young cow 
bird that had been hatched during my absence of 
twenty-four hours, all the eggs of the proprietor re- 
maining. I had not an opportunity of visiting the nest 
for three days, and, on my return, there was only one 
egg remaining, and that rotten. The yellow-throat 
attended the young interloper with the same apparent 
care and affection as if it had been its own offspring. 
u The next year my first discovery was in a blue- 
bird’s nest, built in a hollow stump. The nest con- 
tained six eggs, and the process of incubation was going 
on. Three or four days after my first visit, I found a 
young cow bird, and three eggs remaining. I took the 
eggs out ; two contained young birds, apparently come 
to their full time, and the other was rotten. I found 
one of the other eggs on the ground at the foot of the 
stump, differing in no respect from those in the nest, 
no signs of life being discoverable in either. 
<c Soon after this, I found a goldfinch’s nest with one 
egg of each only, and I attended it carefully till the 
usual complement of the owner were laid. Being 
obliged to leave home, I could not ascertain precisely 
when the process of incubation commenced ; but from 
my reckoning, I think the egg of the cow bird must 
have been hatched in nine or ten days from the com- 
mencement of incubation. On my return, I found the 
young cow bird occupying nearly the whole nest, and 
