THE 
AMERICAN NATURALIST 
VOL XXXIII. June, 1899. No. 390. 
THE EFFICIENCY OF SOME PROTECTIVE 
ADAPTATIONS IN SECURING INSECTS 
FROM BIRDS. 
SYLVESTER: D. (JUDD. 
DurinG the past four years I have been studying the food 
habits of birds in the Biological Survey of the U. S. Depart- 
ment of Agriculture. Owing to the extreme kindness of my 
chief, Dr. C. Hart Merriam, I have now at my disposal data 
accumulated from the examination of the stomach contents of 
fifteen thousand birds. My colleague, Professor F. E. L. Beal, 
has given me invaluable assistance in the preparation of this 
paper. I am also indebted for criticism to Drs. L. O. Howard 
and Chas. Wardell Stiles. Messrs. Schwarz, Banks, Chitten- 
den, and Pratt, of the Department of Agriculture, have been 
most kind in identifying insects. 
The bulk of the insect food of birds consists of grasshoppers 
(Acrididze and Locustidz), noctuid larve, weevils, smaller cara- 
bids, May beetles and their allies, smaller dung beetles (Ontho- 
phagus, Hister, Atænius, and Aphodius), chrysomelids, true 
bugs (Heteroptera), parasitic Hymenoptera (mostly Ichneu- 
monidze), ants, and spiders.? 
1 Included thus for convenience. 
461 
