568 
ECONOMIC RELATIONS OF OUR BIRDS, 
Tabular Summarij of Economic Reflations showing the number of sjjeeimens eat¬ 
ing animal and vegetable f ood, and the number of insects and spiders taken 
from the stomachs, classified as to economic relations under the heads Beneji- 
cicd, Detrimental and Unknown Relations. 
Number and Name of Speci¬ 
mens Examined. 
Of thirteen Black-billed 
Cuckoos examined.. 
13 
3 
11 
OJ 
d 
a 
o 
o 
Classification 
OF Food. 
Ratios Represented by Lines. 
Animal food.... 
Vegetal food.| 
3 
93 
81 
Beneficial .. 
Detrimental 
Unknown. . . 
One Y ell o w - b i 11 e d 
Cuckoo examined... 
0) 
d 
o 
O 
Detrimental 
Unknown... 
Animal food.| 
Vegetal food. 
Beneficial. 
Table showing the number and kinds of insects and spiders eaten by the Cuckoos. 
Number and Name of Speci¬ 
mens Examined. 
Of thirteen Black-billed 
Cuckoos examined.. 
.2 
9 
2 
6 
2 
10 
10 
'd 
d 
o 
O 
70 
Classification 
OF Food. 
13 
03 
10 
26 
53 Adult forms 
Larvae. 
Ratios Represented by Lines. 
Hymenoptera .... 
Caterpillars. 
Beetles 
Orthoptera 
Harvest-men 
1 - 1 — 
— 
1 1 
— 
1 
1 1 
1 
X! 
9 
Cateiiiillars.I^HHI 
One Ye 1 lo w - b i 11 e d 
Cuckoo examined... 
1 
s 
d 
Adult forms. 
1 
o 
9 
Larvae. 
O 
142. CoccYGUS erythrophthalmus (WiLS.), Bd. BLACK-BILLED cuckoo. 
Group II. Class b. 
The Cuckoo is a common summer resident, arriving early in May and witli- 
d rawing again toward the last of September. Its usual haunts are the interior 
of woods, groves and the wooded banks of streams. Frequently it visits the 
grassy swales in marshes where small clumps of willows abound, and during 
the spring it may be seen in orctiards and villages. I know of no insectivorous 
bird so excessively voracious as it, unless it be the next species. The amount 
of material which may be found in its stomach at one time seems out of all pro- 
