NATURAL SCIENCES OF PHILADELPHIA. 211 



" Notes on North American species of Arcliibuteo and Lanius, and 

 Description of a new species of Toucan of the genus Selenidera, by John 

 Cassin." 



" Description of several new North American Reptiles, by E. Hal- 

 Icwell, M. D." 



" Descriptions of Exotic Genera and Species of the Family Unionidse, 

 by Isaac Lea." (For the Journal.) 



" Prodronius descriptionis animalium, &c., by Wm. Stimpson." 



" Observations on a group of Fossil shells found in Tippah County, 

 Miss., with descriptions of fifty-five new species, by T. A. Conrad." 

 (For the Journal.) 



Notes on the North American species of Archihnteo and Lanius, and description 

 of a new species of Toucan, of the genuS Selenidera, Gould. 



BY JOHN CASSIN. 

 Genus Archibuteo, Brelim. Tsis, 1828, p. 1269. 



Of this genus there are three North American species, all of which have been 

 misunderstood and confounded with each other in a greater or less degree by 

 authors. Of these, the most common and best linown species, Archibuteo lar/opus, 

 is one of the few birds of this continent which appears to be absolutely identi- 

 cal with the species of Europe long known by this name, the adult of which 

 has been mistaken by American naturalists, while of the European bird the 

 adult has apparently been unknown to British and French ornithologists, though 

 figured and described by the Germans and others of northern Europe. 



1. Archibuteo lagopus, (Gmelin.) 



Falco lagopus, Gm. Syst. Nat. i. p. 260, (ITSB.) 



Naumann, Vog. Deuts. i. pi. 34, (adult and young;) Reichenbach, Deuchland's 

 Fauna, Birds, pi. xiii. fig. 51, (adult;) Korner, Skandinaviska Foglar, pi. v. fig. 

 15, (adult;) Selby, 111. Brit. Orn. pi. vii. (young;) Gould, B. of Eur. i. pi. 15, 

 (young ;) Wilson, Am. Orn. ir. pi. 33, (young ;) Aud. B. of Am. pi. 422, fig. 2, 

 (adult?) 



Tarsus densely feathered in front to the toes, naked behind ; wings long, tail 

 rather short. 



Adult. Upper parts of body pale cinereous, with i^artially concealed trans- 

 verse bands of white and dark brown ; rump dark umber brown ; head yellowish 

 white with longitudinal stripes of brown frequently tinged with pale reddish : 

 quills dark umber brown, edged externally with ashy, aud with a large space 

 at thc'base of their inner webs, white, with a silky lustre. Under parts white; 

 throat with longitudinal narrow stripes of dark brown; breast with large spots 

 and concealed stripes of reddish brown ; abdomen with numerous narrow bands 

 of brownish black, most conspicuous on the flanks and frequently with a tinge 

 of ashy ; tibi?e and tarsi barred transversely with white and dark brown, and 

 frequently with a tinge of reddish ; under tail coverts white. Upper tail coverts 

 white at base and tipped with brownish black : tail white at base, with a wide 

 subterminal band of black, and about two other bands of black alternating with 

 others of light cinereous, tip ashy white, cere and toes yellow. 



Young. Upper parts light umber brown, many feathers edged with yellowish 

 white and pale reddish, which colors predominate on the head and neck in some 

 specimens. Under parts yellowish white, with a wide transverse band of 

 brownish black on the abdomen, and a few longitudinal lines and spots of 

 the same color on the breast and neck. Quills ashy brown, with a large basal 

 portion of their inner webs white ; tail at its base white, with a wide subter- 

 minal band of light umber brown ; tip white ; tibiae and tarsi pale reddish yellow, 

 with longitudinal stripes and spots of dark brown. 



1857.] 



