THE BOBOLINK. 19 
In view of the fact that the food habits of the bird during migration 
are well known, attention has been directed chiefly in the present 
laboratory investigation to the character of the food taken on the 
breeding grounds. Of 291 stomachs examined (see p. 72), 231 were 
obtained from various points in the North, embracing nineteen States, 
from Massachusetts to Montana, the District of Columbia, and Onta- 
rio. They were taken in the five months from May to September, 
inclusive, but the majority of the September birds whose stomachs 
have been examined may be regarded as belated migrants. The food 
for these five months was found to consist of 57.1 percent animal mat- 
ter and 42.9 percent vegetable. This result would be rather surprising 
but for the fact that only two of the May and nine of the September 
stomachs were collected in the rice fields. The general character of 
the food during the five months is shown in the accompanying diagram 
(fig. 2). 
. MAY JUNE JULY AUG. SEPT. i 
1005 . 5 PORASEASS <T <T 
AN WAS S SS SASS ANNES ALYY SN IAQN SYN SQ QN NOE 
UN ASSAY 
3 CORRG SSSA AAA QQ awd 6 
KE RFAT RNC 
ah\\ NRE G,, 
NW WQS 
= AAS NN NENTS 
NS NE AQQ °° ws WN 
70 BANN <S 
50 
INJURIOUS=—HINSECTS = KER SEED 
40 =< 40 
3 =N 30 
20 = 20 
10 40 
WL 
|_E=uSEFUL=INSECTS = ae 
Fig. 2,—Diagram showing proportions of animal and vegetable food of bobolink in each month from 
May to September inclusive. (The figures in the margins indicate percentages.) 
Of the insect food, as determined by the examination, beetles con- 
stitute nearly 19 per cent. Predaceous species (Carabide), which are, 
broadly considered, useful insects, are represented only by a trace; 
snout-beetles, or weevils (Rhynchophora), amount to 8.9 percent, and 
in May to 20.8 percent; and other beetles, of various families, and all 
