You may perceive in his rear a few stunted cottonwood-trees scattered along the edge of a channel, in which, apparently, water once _was_, but now is not; whilst around him, here and there, is a light-leafed mesquite that stretches forth its slender arms, and appears to invite him to a shade which is but a mockery. Here it was that I first heard the plaintive voice of this bird as he strove to cheer his mate whilst occupied in the tedious task of incubation. “I had passed the hours of noon stretched upon the sand near the well: the thermometer, in the best shade to be obtained, indicating a temperature of 140° to 150°, (_Fahrenheit_); and as the sun began to decline towards the horizon, the first wakeful sound of animal life that greeted my ear was the soft ‘_kaa-wale_,’ ‘_kaa-wale_,’ of this beautiful bird. I turned towards a cluster of mesquite, at the distance of some two hundred yards from which the call seemed to come, but could discern no object in motion. This song was continued, at short intervals, for about an hour; when, at last, one of the birds came forth upon the sand, and was soon followed by its mate. They ran lightly over the sand, and glided into the gully, where they began to search for their evening meal. I followed with my gun and secured them both—they were a male and female, the skins of which I have preserved. This was June 8th. “Later in the season, when a covey is dispersed, the cry for assembling is ‘_qua-el_,’ ‘_qua-el_.’ The voice at all seasons bears much resemblance to that of the _California Partridge_—having, in its intonation, no similarity to the whistle of the Virginia or common partridge. “The crops of those killed at the Alamo, and thence to the Colorado, were filled with the leaves of the mesquite, which seemed to be their principal food, though in some were found remains of coleopterous insects. In some of those killed near the river I found the wild gooseberry. “The dimensions of this species, given by Gould in his ‘Odontophorinæ,’ are, (? skin) length 9¾ inches; wing, 4½; tail, 4. By Dr. Gambel, (Proc. Acad. Nat. Sci., Philada., I. p. 260,) length, over 10 inches; wing, 4½; tail, 4½. “Those I obtained in California were as follows, (measured immediately when killed): “♂ length, 10½ to 11⅜; wing, 4½; tail, 4½. “♀ “ 10⅜ to 10⅝; wing, 4½; tail, 4½.” The identical pair of birds alluded to in this excellent and satisfactory history is represented in our plate; and the specimens, with many others collected by this gentleman, are now in the collection of the Philadelphia Academy. Fine specimens of this bird are also now in the national collection at Washington, and were collected by Dr. Woodhouse, while attached to the party under command of Captain Sitgreaves, which surveyed the rivers Zunia and the Colorado of the west. DESCRIPTION AND TECHNICAL OBSERVATIONS. Genus Callipepla. Wagler in Isis, 1832, p. 277.