12 The Regulative Action of Birds upon Insect Oscillations. 
{ 
COTURNICULUS PASSERINUS, Wils. YELLOW- WINGED SPARROW. 
A single specimen of this bird, shot in 1881, contained spiders 
thirty per cent., seeds of pigeon grass (, Setaria ) fifteen per cent., 
an unrecognized beetle five per cent., and some undetermined 
caterpillars, certainly not canker-worms. 
Spizella domestica, Bart. Chipping Sparrow. 
This species was not common in the orchard in 1881, and only 
a single specimen was obtained; but in the following year it was 
found much more abundant, and seven additional were taken. 
About one-third of the food consisted of caterpillars, half of 
which were recognizable as canker-worms. A large number of 
gnats (twenty-eight per cent.), nearly as many Coleoptera, (prin- 
cipally Scarabaeidge, including nine per cent, of Anomala), and six 
per cent, of Hemiptera, are all the other noteworthy items. 
Spizella agrestis, Bart. Field Sparrow. 
This species was less abundant than the preceding, and was 
represented by only three specimens. With the exception of five 
per cent, of gnats, and one of Hemiptera, the food of this bird 
was equally divided between Lepidoptera and Coleoptera. 
Nearly half the former consisted of canker-worms, while the 
Coleoptera were represented by Histeridae, Scarabaeidae (chiefly 
the scavengers), Monocrepidius and Rhynchophora. 
Spiza Americana, Gmel. Black-throated Bunting. 
This bird was the most abundant species in 1881, though but 
few were seen during the following May. Eleven were shot at 
the first visit and three at the second. With the exception of a 
little wheat eaten by two of the birds, and a trace of undeter- 
mined seeds, the food consisted almost entirely of insects and mol- 
lusks, eighty-eight per cent, of the former and six of the latter 
(Helix). Ten of these birds had eaten canker-worms, which 
made forty- three per cent, of the food of the entire group; Lepi- 
doptera as a whole composing two-thirds of the food. Among 
the twenty-two per cent, of Coleoptera, we note Harpalus and 
Histeridae, each four per cent., Aphodius and Anomala likewise 
each four per cent., and Sphenophorus and other Rhynchophora, 
two per cent. 
