SP. CHAR. _Adult male_ (17,230, Cape St. Lucas, Lower California; J. Xantus). General plumage uniform sooty-black, purest on the tail, somewhat tinged with chestnut on the rump. Lesser wing-coverts and lateral half of each web of middle coverts, also the tibiæ, rich deep chestnut, perfectly uniform. Upper and lower tail-coverts, and broad basal and terminal zones of tail, pure white, the anterior band concealed (except on outer feathers) by the upper coverts, and about twice the width of the last, which is about 1 inch wide. Tail-coverts with a few irregular narrow shaft-streaks of blackish. Lining of wing deep chestnut, like the shoulders; each greater covert with a black shaft-streak; primaries beneath plain black. Wing, 14.50; tail, 10.00; tarsus, 3.25; middle toe, 2.00. Fourth and fifth quills longest and equal; third considerably shorter; second intermediate between sixth and seventh; first 3.40 shorter than longest. _Adult female_ (42,559, Iztlan, Mexico; Colonel Grayson). Generally similar to the male; the black, however, less pure and more brownish, the chestnut more extended, the whole rump being of this color, the last feathers merely being blackish in the middle. White of tail-coverts without blackish streaks. Wing, 14.60; tail, 10.30; tarsus, 3.25; middle toe, 1.95. _Immature male_ (second year, 50,763, Tepic, Mexico; Colonel Grayson). Upper parts similar to adult, but less uniform; the nape and back with feathers edged with rusty; sides of head and neck very much streaked. Breast and abdomen light ochraceous, with large longitudinal oval spots of black; tibiæ light ochraceous, with rather distant transverse bars of dark rusty-brown; lower tail-coverts ochraceous-white, with black shaft-lines. Rufous on the wings more extended and more broken; none on the rump. Terminal band of tail narrower and less sharply defined than in adult; inner webs of primaries with basal two-thirds white, irregularly mottled with dusky. “Iris chestnut-brown; cere, chin, and space round the eyes yellow.” _Immature female_ (second year, 15,260, Fort Buchanan, New Mexico; Dr. Irwin). Black spots beneath larger and more irregularly defined; tibiæ strongly barred with dark rufous; posterior edge of basal band of tail much broken. HAB. Middle, or northern tropical, America, from the Isthmus of Panama northward into the southern United States; Mississippi (AUDUBON); Texas (Mus. S. I.; DRESSER); Arizona (COUES). Localities: Guatemala (SCL. Ibis, I, 216). LIST OF SPECIMENS EXAMINED. National Museum, 13; Philadelphia Academy, 3; Cab. G. N. Lawrence, 2; Coll. R. Ridgway, 1. Total, 19. _Measurements._