Family XLV. COLYMBINAE. DIVERS AND GREBES.
GENUS II. PODICEPS, Lath. GREBE
Bill about the length of the head, or shorter, straight, rather stout, much compressed, tapering, pointed; upper mandible with the dorsal line declinate and more or less convex toward the end, the ridge convex, the sides erect and somewhat convex, the edges sharp and inflected, the tip narrow; nasal groove rather long, extending to nearly half the length of the mandible, feathered at the base; nostrils linear-elliptical, basal, rather small, pervious; lower mandible with the angle long and extremely narrow, the dorsal line ascending and straight, the sides erect and slightly convex, the edges sharp and involute, the tip acute. Head of moderate size, oblong, narrowed before; neck rather long and slender; body long, depressed. Feet short, large, placed close to the extremity of the body; tibia feathered to the joint; tarsus extremely compressed, its anterior edge with a row of small scutella, the sides broadly scutellate, the posterior ridge with a double row of small prominent scales; toes four, first very small, with a posterior membrane, fourth longest, all scutellate, the anterior connected at the base by membranes, and having on both sides an expanded web-like margin, marked with oblique lines. Claws flat, that of the third toe broadest. Plumage very soft and blended, on the lower parts dusky. Wings small, acute, curved, the second primary longest, the first little shorter; secondaries short and rounded. Tail a slight tuft of loose feathers, fourteen in number. Tongue slender, trigonal, pointed; oesophagus of moderate width; proventriculus very large, ovate; stomach extremely large, roundish, its muscular coat thin; the epithelium thick, soft, rugous; a small pyloric sac; intestine of moderate length and width; coeca rather long, slender; cloaca very large, globular. Bronchi with the rings entire and ossified.