280 [February, 



with rufous. It is labelled as having been obtained on the Rio Grande, in the 

 territory of Utah. 



13. Buteo Swainsonii, Bonaparte. 



In the collection made by Mr. Kreutzfeldt, of Lieut. Beckwith's party, there 

 are three specimens undoubtedly of this species, and the first that I have ever 

 seen. 



This species is a typical Buteo, and though I cannot regard it as identical with 

 the European Buteo vulgaris, it is more nearly related to it than is any other 

 American species with which I am acquainted. Like that species, too, it pre- 

 sents a marked variation in the colors of different specimens, the present three 

 being all unlike each other in a considerable degree. One specimen is almost 

 exactly of the form, dimensions and colors as originally described and figured by 

 Mr. Swainson, in Fauna Boreali Americana, Birds p. 47, pi. 27, and stated by 

 him to have been made (both description and figure) from a male bird. On the 

 specimen described by Mr. Swainson, as a female, (in the work just mentioned, 

 p. 49,) I shall venture some observations below. 



The first and apparently most mature specimen is as follows : 



Bill wide at base, compressed towards the tip, edge of the upper mandible 

 lobed, cere large. Wing long, third quill longest, tail moderate, rather wide, 

 truncate, tarsus feathered in front for nearly half its length, naked behind, bare 

 portion presenting in front about twelve transverse scales, toes rather short, 

 claws strong. Entire upper parts dark brown, nearly black in the middle of 

 many feathers, and paler on their edges. Quills brownish black, with wide, 

 transverse bands of cinereous on their inner webs, becoming paler and nearly 

 pure white towards their bases. Tail brown* tinged with ashy, and having 

 transverse bands of a darker shade of brown, the subterminalof which is widest, 

 tip edged with white. Throat white, with longitudinal lines of dark brown, 

 neck before and breast ashy brown, some of the feathers edged with reddish. Other 

 under parts white, nearly pure on the under tail coverts, and strongly tinged, 

 and with transverse, irregular bars of rufous on the tibiae, abdomen with nume- 

 rous irregular and imperfect narrow Transverse bars of brown tinged with red- 

 dish. Under wing coverts white, with a few spots and transverse stripes of 

 brown. Bill dark slate color, tarsi and toes yellow. 



Dimensions. Total length (of skin,) 2H inches, wing 16, tail 5 h, tarsus 2 

 inches. 



The second specimen has the upper parts as just described, but darker. 

 Throat white, faintly tinged with yellowish, (without stripes of brown,) breast 

 dark brown, {nearly black), and the other under parts pale rufous, darker on the 

 tibiae, and with transverse stripes of brown on all the under parts less numer- 

 ous than on the abdomen of the preceding specimen, and more irregular. Total 

 length (of skin) 20 inches, wing lSg, tail 81. 



The third specimen has the upper parts about the same shade of brown as 

 the first described above, but with the tail darker, and the transverse bands 

 more indistinct. Throat white, with a few longitudinal lines of black, \eck be- 

 fore and breast light rufous, some of the feathers ashy brown in the middle, 

 other under parts white nearly pure and unspotted on the lower part of the ab- 

 domen and on the under tail coverts, tinged with very pale reddish on the tibiae, 

 upper portion of abdomen and flanks nearly pure white with a few spots and 

 transverse bars of fulvous and dark brown. Total length (of skin) 20 inches, 

 wing \b\, tail 8 inches. 



In all these specimens the color of the neck before and of the breast, may 

 be said to form a wide uninterrupted transverse belt or band, and is a very con- 

 spicuous and apparently constant character. The sexes of these specimens are 

 not stated in the labels attached to them. 



The tail in the specimens above varies merely in shade of the same brown 

 color. In the first and apparently the most mature specimen, it is strongly 

 tinged with cinereous. There is no tendency to become red in the tail of either 

 specimen. 



