Sicker, the popular name of the soft-rayed fishes of the carp family (cyprinidoe) included in the genus catostomns (Lesueur). They are characterized by a single dorsal, three rays in the gill membrane, smooth head and gill covers, jaws without teeth and retractile, mouth beneath the snout, and lips plaited or lobed suitable for sucking; there are comb-like teeth in the throat; the intestine is very long, and the air bladder divided into two or more parts. There are about 30 species in the fresh-water rivers and lakes of North America; they rarely take bait, and are very tenacious of life. The common sucker (C. Bostoniensis, Les.) is 8 to 15 in. long, of a brownish color, olive on the head, reddish with metallic lustre on the sides, and white below; it is common in New England and the middle states. The chub sucker (G. giblosus, Les.) is 7 to 12 in. long, dark brown above, golden greenish yellow on the sides, anterior part of abdomen whitish, and fins dark; body convex in front of dorsal, and sides of head sometimes spiny or tnberculated; it is common in the ponds of the New England and middle states.

Large species from the northern regions have been described by Richardson and Agassiz. Among the larger speoies of the western rivers are the Missouri sucker (C. elongatus, Les.), 2 to 3 ft. long, in the Ohio river, black on the back, and hence called black horse and black buffalo; and the buffalo sucker (G. bubalus, Raf.), of about the same size, in the Ohio, Mississippi, Missouri, and their tributaries, brownish above, bronzy on the sides, and whitish on abdomen.

Common Sucker (Catostomus Bostoniensis).