Bill long, very slender, straight or arched, somewhat depressed at the
base, subcylindrical, flexible, acute. Head rather large; neck of
moderate length; body moderately robust. Feet very short, rather
stout; tarsus extremely short; toes of moderate size; the anterior
coherent at the base, and nearly of equal length, the hind toe
articulated high on the tarsus; claws rather long, arched, much
compressed, very acute. Plumage compact above, soft and blended
beneath, often with metallic lustre; wings very long, extremely
narrow, falciform, with the first quill longest, the other primaries
rapidly diminishing; secondaries extremely short. Tail various, of ten
feathers. Tongue very long, slender, with two flat, thin-edged
terminal filaments, and extensile by means of the elongation of the
hyoid bones, which curve over the head to the fore part of the
forehead, and with their muscles slide in a groove, like those of the
Woodpeckers. Œsophagus narrow, considerably enlarged about the
middle; stomach extremely small, roundish, moderately muscular, its
epithelium dense and longitudinally rugous; intestine very short and
of moderate width; no cœca; cloaca globular. Trachea simple, but
divided very high up on the neck, so that the bronchi are of excessive
length, with a large pair of inferior laryngeal muscles.
GENUS I. TROCHILUS, Linn. HUMMINGBIRD.
Bill long, subulate, depressed at the base, cylindrical, straight, or
slightly arched, flexible; upper mandible with the ridge narrow at the
base, convex in the rest of its extent, the sides sloping, the edges
soft; lower mandible with the angle extremely acute and elongated, the
sides erect, the tip acute. Nostrils linear, with a membranous flap
above. Head small; neck short; body moderately stout. Feet very short;
middle toe scarcely longer than the rest. Plumage rather blended and
glossy above. Wings very long, extremely narrow; tail rather long,
broad, nearly even. The other characters as above.