Diagnosis. Shell medium size; thick shelled; broadly trochiform, spire short coniform; whorls convex to almost straight, periphery, base rounded; smooth, only with microscopic growth lines; broardly umbilicate; outer lip sharp, oblique; columella concave with one tubercle at base; operculum with spiral tufts on each volution. Remarks. Norrisia is a monotypic genus, clearly distinct based on radular characters. The single species of the genus is unlike any other.