Redescriptions of Crotonia cophinarius (Mich., 1908) and of C. unguifera (Mich., 1908) are based on the original collections in the British Museum (Nat. Rist.), and lectotypes are designated. A number of other species belonging to this genus are also described, namely C. chiloensis n. sp. and C. jiagellata (Balogh and Csiszar) from Chile, C. lanceolata n. sp. and C. brassicae n. sp. from St. Helena, and C. melanesiae n. sp. from the New He brides. The genus is distinguished from the related H olonothnts mainly by the deficient character of the notogastral chaetotaxy and the development of setal apophyses. Comparisons between ten species presently assigned to the genus C1 otonia suggest that two distinct morphological groupings, designated the cophinari~ts and ungttijera groups respectively, may be recognized. The zoogeographical distribution of both of these groupings is discontinuous, but may represent a relie of an earlier, more extensive, continuous pattern.