ECONOMIC RELATIONS OF OUR BIRDS. 
663 
136. Empidonax flavivexNTRIS, Bd. YELLOW-BELLIED FLYCATCHER. 
Group II. Class a. 
A single specimen of this species was oljtained at Worcester, July 26, 1876. 
Dr. Hoy identified it at Racine, during the summer of 1860. Mr. Nelson speaks 
of it as a common migrant in Northeastern Illinois. None of the fragments of 
five insects found in its stomach were identified. 
Fajuly CAPIUMULGIDjE: Goatsuckeks. 
Fig. 181. 
YiiGwn-uxws. {Chordeiles popetue). After Bd., Br. and Ridg. 
Tabular Summary of Economic Relations showing the number of specimens 
eating animal and vegetable food, and the number of insects taken fro7n 
the stomachs, classified as to economic relations under the heads Beneficial, 
Detrimental and Unknown Relations. 
Number and Name op Speci¬ 
mens Examined. 
Classification 
OF Food. 
Ratios Represented by Lines. 
2 
Animal food. 
B 
Of two Whippoorwills 
escamined. 
•^3 
Vegetal food. 
1 
Beneficial . 
2 
M 
O 1 
0 
10 
Detrimental. 
Unknown. 
1 
2 
1 
1 
5 
Animal food . 
BOB 
Of five Night-hawks 
examined. 
Vegetal food .... 
1 
s 
*5 
1 
I Beneficial . 
1 
2 
5 
o 
o 
8 
S3 
Detrimental. 
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ihawB 
