406 U. S. p. R. R EXP. AND SURVEYS — ZOOLOGY — GENERAL REPORT. 



Family F JITN GILLID A E . 



Primaries nine. Bill very short, aljniplly conical and robust. Commissure strongly angulated at base of bill. Tarsi 

 Bcutellate anteriorly, but the sides witii two undivided plates meeting behind along the median line, as a sharp posterior ridge. 



The systematic arrangement of the fringilline hirtls of the United States is more difficult than 

 that of any other group, owing to the large number of species closely related to each other and 

 exhibiting endless though minute variations in structure and form. Nearly all authors regu- 

 larly avoid committing themselves by an attempt at the definition of their different divisions, 

 giving only the names of types as indicative of their meaning. I have, theiefore, been able to 

 derive no aid from ornithological publications in arranging the species, and have been obliged 

 to work out the whole subject anew from the beginnings as far as North American species are 

 concerned. 



In the system adopted I do not claim any very natural combination of species into genera, 

 nor of genera into sub-families ; all I have aimed at is to present a convenient artificial scheme 

 by which the determination of the species may be facilitated. The means at my command are 

 manifestly insufficient for the satisfactory solution of a problem which has puzzled the best 

 ornithologists of the day, with all possible resources at their command in the way of specimens 

 and books. 



I divide all the United States species into four sub-families, briefly characterizablo as follows : 



CoccoTHRAUSTiNAE. — Bill Variable, from enormously large to quite small ; with the base of the 

 upper mandible almost always provided with a close pressed fringe of bristly feathers (more or 

 less conspicuous) concealing the nostrils. Wings very long and pointed, usually one-half to 

 one-third longer than the forked or emarginate tail. Tarsi short. 



Spizellinae. — Embracing all the plain colored sparrow-like species marked with longitudinal 

 stripes. Bill conical, always rather small; both mandibles about equal. Tarsi lengthened. 

 Wings and tail variable. Lateral claws never reaching beyond the base of the middle claw. 



Passerellinae. — Sjiarrow-like species with triangular spots beneath. Legs, toes, and claws 

 very stout ; the lateral claws reaching nearly to the end of the middle ones. 



Spizinae. — Brightly colored species usually without streaks. Bill usually very large and 

 much curved; lower mandible wider than the upper. Wings moderately long. Tail variable. 



Sub-Family COCCOTHRAUSTINAE. 



Wings very long and much pointed ; generally one-third longer than the more or loss forked tail ; first quill usually nearly 

 as long, or longer than the second. Tertiaries but little longer, or equal to the secondaries, and always much exceeded by the 

 primaries. Bill very variable in shape and size, tlio upper mandible, however, as broad as the lower; nostrils rather more 

 lateral than usual ; and always more or lees concealed by a series of small bristly feathers applied along the base of the upper 

 mandible ; no bristles at the base of the bill. Feet short and rather woak. Hind claw usually considerably longer than the 

 middle anterior one ; sometimes nearly the same size. 



In the preceding paragraph I have combined a number of forms, all agreeing in the length 

 and acuteness of the wing, the bristly feathers along the base of the bill, the absence of con- 

 spicuous bristles on tlie sides of the mouth, and in the shortness of the feet. They are all 

 strongly marked and brightly colored birds, and usually belong to tlie more northern regions. 



The species of tlie genera all vary remarkably in the shape and size of tlie bill, whicli hero 

 is of secondary importance to the character of tlie wing, tail, and feet. Indeed, I am inclined 



