484 



U. S p. K. E. EXP. AND SUKVEYS — ZOOLOGY — GENERAL KEPORT. 



PEUCAEA, Audubon. 



Peucaea, Audubon, Synopsis, 1839. Type Fringilla aestivalis, 



Ch. — Bill moderate. Upper outline and commissure decidedly curved ; gonys nearly straight. Legs and feet small ; the tarsus 

 about equal to the middle toe ; the lateral toes equal, their claws falling considerably short of the middle one ; the hind toe 

 rcacliing about to the middle of the latter. The outstretched feet reach only to ihe middle of the tail. The wing is very short, 

 reaching only to tlio base of the tail ; the longest tertials do not exceed the secondaries, while both are not much short of the 

 primaries ; tlie outer tliree or tour quills are graduated. The tail is considerably longer than the wings ; it is much graduated 

 laterally ; the feathers, though long, are peculiarly narrow, linear, and elliptically rounded at the ends. 



Color beneath plain whitish or brownish, with a more or less distinct dusky line each side of the chin. Above with broad obso- 

 lete brown streaks or blotches. Crown uniform, or the feathers edged with lighter. Inner tail feathers with obsolete transverse 

 dusky bars. 



This is a very well defined group, with a curved upper rnandible ; short toes ; very sliort and 

 much rounded wings, less than the tail ; a long, much graduated tail, with the feathers narrow, 

 linear, and elliptical at the end. This character of the tail, with that of the unspotted under 

 parts and black streak on each side of the chin, and the yellow edge to the wings in two of the 

 species, are all strong distinctive features. 



Synopsis of species. 



A. Maxillary black streak narrow; edge of wing yellow (inconspicuously.) Head above streaked. 



Feathers above with the central portion dark chestnut ; those of the back with broad 

 streaks of brown. Throat, breast, and sides tinged with yellowish ash P. aestivalis. 



Feathers above paler ; those of back with narrow central streaks of brown, or else 

 wanting. Beneath paler; throat nearly white P. cassinii. 



B. Maxillary stripe very distinct. Head above nearly uniform reddish. Edge of wing 

 grayish white P. rujiceps. 



Comparative measurements of species. 



PEUCAEA AESTIVALIS, Cabanis. 



Bachman's Finch. 



Fringilla aestivalis, Light. Verz. Doubl. 1823, 25, No. 254.— Bonap. Conspectus, 1850, 481. 



Peucaea aestivalis, Cabanis, Mus. Hein. 1850, 132. 



FringiUa baclimani, AuD. Orn. Biog. II, 1834, 3G6 ; pi. 165. 



.^mmodromus bnchmnni, Bon. Li.st, 1838. 



Peucaea baclimam, Aud. Syn. 1839.— Is. Birds Am. Ill, 1841, 113; pi. 176.— Bon. Consp. 1850, 481. (Type.) 



Fiingillu aestiva, Nutt. I, 9d ed. 1840, 568. 



" Summer Jincli, Latham, Synopsis, 2d ed. VI, 136." Nuttall. 



