6. Heliosestrum contiguum, Haeckel.
Haliomma contiguum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 74, Taf. xxvii. fig. 5.
Disk with smooth surface, four times as broad as the medullary shell. Pores irregular, roundish, touching, with very thin bars; nine to ten on the radius. Eight marginal spines (often seven or nine) conical, half as long as the radius, twice as long as broad, without a connecting equatorial girdle.
Dimensions.—Diameter of the disk 0.17, of the medullary shell 0.04; length of the radial spines 0.04, basal breadth 0.02.
Habitat.—Fossil in Barbados.
7. Heliosestrum irregulare, n. sp.
Disk with smooth surface, four times as broad as the medullary shell. Pores irregular, roundish; nine to eleven on the radius. Eight conical radial spines of irregular size and distribution, often seven or nine, about as long as the radius of the disk (in some cases longer, in others shorter). No connecting equatorial girdle.
Dimensions.—Diameter of the disk 0.2, of the medullary shell 0.05; length of the radial spines 0.1, basal breadth 0.02.
Habitat.—Central Pacific, Stations 270 to 272, depth 2425 to 2925 fathoms.