Читать книгу A History of North American Birds, Land Birds. Volume 3 - Robert Ridgway - Страница 15
Family FALCONIDÆ.—The Falcons
ОглавлениеChar. Eyes directed laterally, and eyelids provided with lashes. Toes invariably naked, and tarsus usually naked and scutellate (feathered only in Aquila and Archibuteo). Outer toe not reversible (except in Pandion). Head never with ear-tufts, and never wholly naked (except in the Vulturinæ, of the Old World).
The above characters are about the only readily observable points in the external anatomy in which the Falconidæ differ strikingly from the Strigidæ and Cathartidæ, and may serve to distinguish the birds of this family from those of the two others. The osteological characters, however, as expressed on page 1328, are more decided and important in a taxonomic point of view, and serve to separate the Hawk family as a well-defined group.
In the following treatment of the North American Falconidæ, I confine that part relating to the systematic arrangement strictly to the species embraced within the province of our work, for the reason that in a forthcoming monograph of all the American species I hope to present a systematic classification based upon the species of the whole world. All preliminary details regarding the general characteristics and distinctive peculiarities of the family, as well as all discussions and generalizations upon the subject, will therefore be omitted here.
The following synopsis of the North American genera is intended as an artificial arrangement which may enable the student to identify, by simple and readily understood characters, the forms belonging to this country.40
40
As in the case of the Strigidæ, my determinations of the North American species of Falconidæ were furnished, according to request, to Dr. Coues, for use in his “Key to North American Birds.” (R. R.)
