COW BUNTING. 
81 
incumbent than the other.* This principle would scarcely apply to the 
eggs of the Blue-bird, for they are nearly of the same size ; if there 
be any difference it would be in favor of the eggs of the builder of the 
nest. How do the eggs get out of the nest'. Is it by the size and 
nestling of the young Cow-bird? This cannot always be the case; 
because in the instance of the Blue-bird's nest in the hollow stump, the 
cavity was a foot deep, the nest at the bottom, and the ascent perpen- 
dicular ; nevertheless the eggs were removed although filled with young 
ones ; moreover, a young Cowpen finch is as helpless as any other 
young bird, and so far from having the power of ejecting others from 
the nest, or even the eggs, that they are sometimes found on the ground 
under the nest, especially when the nest happens to be very small. I 
will not assert that the eo'irs of the builder of the nest are never 
hatched ; but I can assert that I have never been able to find one 
instance to prove the affirmative. If all the eggs of both birds were to 
be hatched, in some cases the nest would not hold half of them ; for 
instance, those of the Sparrow, or Yellow-bird. I will not assert that 
the supposititious egg is brought to perfection in less time than those 
of the bird to which the nest belongs ; but from the fact stated, I am 
inclined to adopt such an opinion. How are the eggs removed after the 
accouchement of the spurious occupant ? By the proprietor of the 
nest unquestionably ; for this is consistent with the rest of her economy. 
After the power of hatching them is taken away by her attention to 
the young stranger, the eggs Avould be only an encumbrance, and there- 
fore instinct prompts her to remove them. I might add, that I have 
sometimes found the eggs of the Sparrow, in which were unmatured 
young ones, lying near the nest, containing a Cowdfird, and therefore 
I cannot resist this conclusion. Would the foster parent feed two 
species of young at the same time ? I believe not. I have never seen 
an instance of any bird feeding the young of another, unless immedi- 
ately after losing her own. I should think the sooty looking stranger 
would scarcely interest a mother while the cries of her own offspring, 
always intelligible, were to be heard. Should such a competition ever 
take place, I judge the stranger would be the sufferer, and probably the 
species soon become extinct. Why the lex naturae conservatrix should 
decide in favor of the surreptitious progeny is not for me to determine. 
" As to the vocal powers of this bird, I believe its pretensions are 
very humble, none of its notes deserving the epithet musical. The sort 
of simple cackling complaint it utters at being disturbed, constitutes 
also the expression of its pleasure at finding its companions, varying 
* The ingenious writer seems not to be aware that almost nil birds are in the 
habit, while sitting, of changing the eggs from the centre to the circumference, and 
vice versa, that all of them may receive an equal share of warmth. 
Vol. II.— G 
