Diagnosis: Tentacles with two pairs of digits. Deposits large tables (0.15–0.27mm diameter), with high spires composed of three converging rods.

Type Species: Trochostoma albicans Theel.

Hedingia albicans (Theel)

Trochostoma albicans Theel, 1886a, p 44, Pl. XI, fig. 3.

Trochostoma albicans var. glabra Theel, 1886a, p. 46; Koehler and Vaney, 1905, p. 89; Perrier, 1902, p. 526, Pl. 22, figs. 7–8.

Caudina arenata var. armata Theel, 1886b, p. 17; Gerould, 1897, p. 19, Pl. III, figs. 34–37.

Caudina albicans: Clark, 1907, p. 174, Pl. X, fig. 12; Deichmann, 1930, p. 201, Pl. 24, fig. 1; Heding, 1931, p. 283.

Haplodactyla albicans: Heding, 1935, p. 65, Pl. IV, fig. 9, Pl. V, fig. 17, Pl. VIII, fig. 10.

Hedingia albicans: Deichmann, 1938, p. 112; Madsen, 1953, p. 167; Deichmann, 1940, p. 216.

Material Examined: None.

Remarks: Occurs off New Zealand, south of Iceland, off the north-east coast of U.S.A., the Cape Verdes, Mediterranean Sea, Bay of Bengal in depths ranging from 500 metres to 3,200 metres (Madsen, 1953).