or 
for) 
USEFUL BIRDS. 
The number of insects consumed daily by young birds in 
their nests is difficult of estimation, because of the variation 
. in size among insects and the great difference in size between 
the mature insect and the newly hatched larva. Five hun- 
dred of the young larve of a moth might occupy less space 
in the stomach of a bird than would the moth itself; while a 
thousand aphids might take no more room than a full-grown 
caterpillar.. Nevertheless, many estimates have been made, 
based on known data, as to the number of insects fed to 
young birds. 
The introduced House Sparrow (Passer domesticus), com- 
monly called the English Sparrow, undoubtedly eats fewer 
insects, here, in proportion to the rest of its food than any of 
our smaller native-birds. The young are fed very largely on 
grain and other non-insectivorous food. Still, a Sparrow’s 
nest in the city of Paris is said to have contained seven hun- 
dred pairs of chafer wing-cases.! 
Mons. P. Pélicot gives a table of the estimates, made by 
several foreign authors, of the numbers of insects eaten by 
Sparrows in a given time. These approximations vary from 
that of Blatin, who estimates that two Sparrows will destroy 
twelve hundred chafers in twelve days, to that of Tschudi, 
who believes that a single Sparrow will destroy fifteen hun- 
dred larve within twenty-four hours.” 
Bradley mentions watching a bird’s nest and discovering 
that five hundred caterpillars were consumed in one day.® 
He says (according to Samuels) that a pair of Sparrows 
will destroy thirty-three hundred and sixty caterpillars for 
a week’s family supplies. A single pair of Sparrows is 
reported to have carried to the nest five hundred insects in 
an hour. 
These statements may be exaggerated, but if they approx- 
imate the facts, what immense numbers of insects must be 
+ Notes on Recent Progress of Agricultural Science, by David A. Wells. Re- 
port (on Agriculture) of the United States Commissioner of Patents, 1861, p. 323. 
? A Favorable View of the English Sparrow, a Review of ‘‘Un Passereau 
a Protéger,’”’ Insect Life, Riley and Howard, Vol. IV, 1891, p. 153, published by 
the United States Department of Agriculture. 
5 Birds and Bird Laws, by J. R. Dodge. Annual Report of the United States 
Commissioner of Agriculture, 1864, pp. 436, 437. 
