340 MICHIGAN BIRDj{LIFE. 
TECHNICAL DESCRIPTION. 
Toes two in front, two behind; tail of long, soft feathers, much graduated. | 
Adult: Upper mandible mainly black, its edges and most of the lower mandible yellow; 
entire upper parts brownish gray or olive gray, often with a bronzy luster; under parts 
pure white; inner webs of most of the primaries rufous or cinnamon; middle tail-feathers 
like the back, the rest black with abrupt and broad white tips. Young: Similar, but 
feathers of upper parts usually with rusty or ashy tips, and tail-feathers with smaller and 
less abrupt white patches. 
Length 11 to 12.70 inches; wing 5.40 to 5.80; tail 6 to 6.15. 
162. Black-billed Cuckoo. Coccyzus ery hropthalmus (Wils.). (388) 
Synonyms: Rain Crow, Kow-Kow.—Cuculus erythrophthalmus, Wils., 1811, and 
authors generally. 
Figure 86. 
So similar to the Yellow-billed Ctickoo in appearance, habits and note 
that the two are very generally confused. The present species shows no 
yellow on the bill, which is nearly black, has a circle of bare red skin about 
the eye, little or no cinnamon in the wing, and the outer tail-feathers only 
lightly tipped with white. (Compare figures 84 and 86.) 
Distribution.—Eastern North America, west to the Rocky Mountains, 
breeding north to Labrador, Manitoba and eastern Assiniboia; south, in 
winter, to the West Indies and the valley of the Amazon. 
In Michigan the Black-billed Cuckoo has nearly the same distribution 
as the Yellow-billed Cuckoo, except that it is equally abundant all over 
the state, whereas the Yellow-billed 
species is apparently less common 
in the northern half. The two 
species are also so similar in general 
habits that most of what has been 
written in the preceding pages is Fig. 86. Tail of Black-billed Cuckoo. 
applicable to the present bird. It From Hoffmann’s Guide. 
arrives from the south at about the Gouttesy of Houghton, Mittin & Co. 
same time, nests in much the same way and at the same time, and 
moves southward again in the fall together with the Yellow-billed species. 
Although a few field naturalists profess to be able to discriminate the 
notes of the two species, most good observers agree that this is impossible. 
Bendire says that it is impossible to distinguish its call notes positively 
from those of the Yellow-billed Cuckoo, and Mr. E. P. Bicknell, one of 
our best authorities on the notes of birds, states that he has been unable 
to find any constant differences. The nests of the two species are likewise 
extremely similar, but the Black-billed is the smaller bird and lays the 
smaller egg; moreover the eggs average deeper in color, the shade being 
described by Ridgway as glaucous-green or verditer-blue. They average 
1.11 by .78 inches, and usually present the peculiar mottled appearance 
already mentioned under the preceding species. 
This bird has been charged with robbing the nests of other birds, precisely 
as in the case of the Yellow-billed Cuckoo, and although the charge lacks 
recent substantiation there may be some truth in the accusation. On the 
other hand, it is equally destructive to injurious insects, on which it feeds 
constantly and voraciously, consuming immense numbers of hairy cater- 
pillars, bugs, beetles, grasshoppers and other injurious species. A single 
