NATURAL HISTOHY 01* SELBOENE. 
07 
may it not be owing to the dams being engaged in incubation, while 
the young are concealed by the leaves ] 
Many times have I had the curiosity to open the stomachs of wood- 
cocks and snipes ; but nothing ever occurred that helped to explain to 
me what their subsistence might be : all that I could ever find was a 
soft mucus, among which lay many pellucid small gravels. 
I am, &c. 
LETTEE IV. 
TO THE SAME. 
Selborne, Feb. IQth, 1770. 
Dear Sir,— Your observation that " the cuckoo does not deposit its 
egg indiscriminately in the nest of the first bird that comes in its way, 
but probably looks out a nurse in some degree congenerous, with whom 
to intrust its young," is perfectly new to me ; and struck me so forcibly, 
that I naturally fell into a train of thought that led me to consider 
whether the fact was so, and what reason there was for it. When I 
came to recollect and inquire, I could not find that any cuckoo had ever 
been seen in these parts, ex- 
cept in the nest of the wag- 
tail, the hedge-sparrow, th^ 
titlark, the white-throat, and 
the redbreast, all soft-billed 
insectivorous birds. The ex- 
cellent Mr. Willughby men- 
tions the nest of the Palumbus 
(ring-dove), and of the frin- 
gilla (chaffinch), birds that 
subsist on acorns and grains, 
and such hard food : but 
then he does not mention 
them as of his own know- 
ledge ; biit says afterwards 
that he saw himself a wagtail 
feeding a cuckoo. It appears 
hardly possible that a soft-billed bird should subsist on the same food with 
the hard-billed : for the former have thin membranaceous stomachs suited 
to their soft food ; while the latter, the granivorous tribe, have strong 
muscular gizzards, which, like mills, grind, by the help of small gravels 
and pebbles, what is swallowed. This proceeding of the cuckoo, 
of dropping its eggs as it were by chance, is such a monstrous outrage 
on maternal affection, one of the first great dictates of nature ; and such 
a violence on instinct ; that, had it only been related of a bird in the 
Brazils, or Peru, it would never have merited our belief. But yet, 
should it farther appear that this simple bird, when divested of that 
natural a-ropy^ that seems to raise the kind in general above them- 
selves, and inspire them with extraordinary degrees of cunning and 
address, may be still endued with a more enlarged faculty of discerning 
H 
