“The favorite haunts of this species are the broad prairies, over which it may be seen generally flying or coursing around in quest of its prey, or occasionally perched in repose, but very carefully keeping out of the range of the gun. It is one of the most shy of our Hawks, and I have never known an instance of its visiting the vicinity of the farm-house, or disturbing the domestic poultry, as is done by nearly all other of our birds of the Falcon kind, much to the disadvantage of their reputation with our farmers and housewives. The present bird at least saves his character in that respect, for he never comes near, and prefers also that no one shall come near him. “The prey of this species is principally Grouse, Quails, and other birds; but when opportunity offers, he does not disdain field-mice, or even snakes. The Pinnated Grouse, or Prairie Hen, as it is universally called in our region of country (_Tetrao cupido_), is his most common food, which, frequenting the prairies habitually, his pursuit of this bird is the cause of his being so constantly seen in such localities. Usually he has little difficulty in procuring a supply sufficient for his wants. I am under the impression that this bird does not rear its young in this part of Wisconsin, as I have never known its nest to be found, though I have of various other species. I have never seen this bird soar in the manner of other Buzzards. It is apparently a visitor only to this part of the State of Wisconsin.” The specimens obtained by Dr. Hoy, one of which is represented in the upper figure in our plate, present considerable similarity in colors; but we have seen one other, which had the colors much darker, and the under-parts especially much marked with black. The latter specimen is represented in our lower figure, and was obtained in the neighborhood of Madison, Wisconsin, by Mr. William Dudley, Secretary of the Wisconsin Natural History Society. The specimen from Utah Territory is almost precisely identical in color with those obtained by Dr. Hoy. We have no further information respecting this interesting species. DESCRIPTION AND TECHNICAL OBSERVATIONS. Genus Buteo. Cuvier, Regne Animal, I. p. 323. (1817.) Buteo Bairdii. Hoy, Proc. Acad., Philadelphia, VI. p. 451. (1853.) Form. Rather smaller than _Buteo lineatus_; compact and robust; wings long, and pointed; third primary longest; tail moderate, rather wide, rounded. Dimensions. Female, total length of skin, 19½ inches; wing, 15; tail, 8 inches, and about an inch longer than the folded wings.