Family VIII. SYLVICOLINAE. WOOD-WARBLERS.
GENUS IV. HELINAIA, Aud. SWAMP-WARBLERS

Bill rather long, being nearly of the same length as the head, straight, or slightly decurved, tapering to a very acute point, much compressed; the upper mandible with the ridge distinct, the sides declinate and flat at the base, the edges somewhat inflected beyond the middle, the notch obsolete; lower mandible with the dorsal line straight, the edges involute, the tip extremely acute. Nostrils oblong; exposed. Feet of moderate length; tarsus about equal to the middle toe and claw, slender, much compressed, with the upper scutella blended; toes slender; claws rather long, moderately arched, slender, much compressed, laterally grooved, extremely acute; plumage soft and blended. Bristles obsolete. Wings rather long, somewhat pointed, the outer three nearly equal, the second longest. Tail of moderate length, nearly even.--Name from [`Elos], a swamp, and [Naio], to inhabit.