Hab. California. Spec. in Mus. Acad., Philada., and Nat. Museum, Washington. Obs. This strongly-marked species bears some resemblance to the European Avocet, and in fact is more closely allied to it than to the only American species previously known. It is, however, a well characterized and distinct bird. The sexes of this species differ somewhat in size, the female being slightly the smaller; and in the male, the dark tints are stronger. The latter is represented in our plate. SYNOPSIS OF NORTH AMERICAN BIRDS. II. ORDER INSESSORES. THE PERCHING BIRDS. A group containing much the greater number of all known birds, almost impossible to characterise in general terms. The birds of this order are, however, generally organized for perching or living in trees, and have the legs and feet moderately developed and formed for grasping. In this group is found the highest development of the bird-like form of animal life. I. TRIBE FISSIROSTRES. THE GOATSUCKERS, SWALLOWS, KINGFISHERS, &c. Bill wide at base; gape very large; feet small, weak; general form adapted to the capture of insects on the wing, and in some of the families to rapid and long-continued flight. This group contains the Goatsuckers (_Caprimulgidæ_), the Swallows (_Hirundinidæ_), the Trogons (_Trogonidæ_), the Bee-eaters (_Meropidæ_), and the Kingfishers (_Halcyonidæ_). I. FAMILY CAPRIMULGIDÆ. THE GOATSUCKERS. Plumage soft, blended, and owl-like. Species generally nocturnal in their habits, or venturing abroad only in the twilight or in the night. Bill small, weak, generally furnished at the base with projecting bristles; gape very wide; feet usually slender and weak; wings generally long, adapted to long-continued flight. This family is represented in all temperate and tropical regions of the world. A. 1. Genus Antrostomus. Gould, Nuttall. Manual of the Ornithology of the United States and Canada, I. p. 739 (second edition, 1840). General form plump and robust; head large; bill short, weak, opening to beyond the eyes; gape very large; nostrils basal, oval, prominent; eyes large; wing long; somewhat pointed; second and third quills longest; legs and toes short, feeble; claw of the middle toe pectinated; tail moderate, wide, generally even at the end; bristles at the base of the bill rigid, long, usually curved at their ends; throat in males with an uninterrupted collar of white; quills with bars of rufous. An exclusively American genus containing six or seven species, more nearly related to typical Caprimulgus than any other birds of this family inhabiting this continent, and almost nocturnal in their habits, venturing abroad only by twilight or in the night.