| NIGHT HAWKS AND WHIP-POOR-WILLS. |
By Dr. R. W. SHUFELDT.
THERE is hardly a season goes by that I am not asked, by some one more or less interested in our native birds, "What is the difference between a night hawk and a whip-poor-will?" Generally the belief is that these two very interesting forms are one and the same species; but this is by no means the case, and a full reply to the question leads us to the consideration of one of the most attractive groups in the entire range of our American avifauna. A number of years ago the writer made a very careful study of the representatives of this family as they occur in our country, and some of the more important facts as brought out by that research will be set forth in the present article. Those most familiar with the habits and anatomical structure of night hawks and whip-poor-wills and their allies place them in a suborder Caprimulgi, which primarily presents us with a family Caprimulgidæ, which family in the United States contains at least the four very distinctive genera Antrostomus, Phalænoptilus, Nyctidromus, and Chordeiles. To the first-named genus belong the true whip-poor-will (A. vociferus), together with Stephen's whip-poor-will, and the chuck-will's-widow of the Southern States, with others. Phalænoptilus Nutalli, the interesting little poor-will of the Western States, is found in the second genus, while Nyctidromus albicollis is representative of the third. Finally, in Chordeiles we have the night hawks, as the common form, C. virginianus, as well as the Western night hawk, the Cuban night hawk, and the Texan night hawk (C. texensis).
To start with these it will be seen that our night hawk and our whip-poor-will belong to two very different genera of the Caprimulgidæ. Not only is this the case, but these two birds are in habits and in structure more widely separated from each other than is the whip-poor-will from any other genus of the family. Indeed, night hawks are quite aberrant types, while, as a matter of fact, none of our United States caprimulgine birds give us any hint of the extraordinary foreign representatives of this suborder, some of which will be referred to further on.
Upon comparing a night hawk with a whip-poor-will we find that, apart from the very well defined difference these birds exhibit in their internal structure and in the general tone and markings of their plumage, there are a few external striking features that ought to enable any person to distinguish one from the other at the most casual glance.
I refer especially to the long, conspicuous bristles projecting from about the mouth of the whip-poor-will, a character almost
