12 The Meguiati've Action of Birds upon Insect Oscillations. 



COTURNICULUS PASSERINUS, Wils. YeLLOW- WINGED SpARROW. 



A single specimen of this bird, shot in 1881, containedPspiders 

 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. 



Spizblla 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 Scarabteidge, 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 Histerid^ie, Scarabteidae (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 

 Histeridas, each four per cent., Aphodius and Anomala likewise 

 each four per cent., and Sphenophorus and other Rhynchophora, 

 two per cent. 



