Mesocena bisoctona, Ehrenberg, 1845, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 78; Mikrogeol., Taf. xxxv., Nr. xviii. figs. 9, 10.
Mesocena binonaria, Ehrenberg, 1845, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 78, loc. cit.
Rings circular, with sixteen teeth; eight stronger teeth regularly disposed on the outer margin, alternating with these eight smaller teeth on the inner margin.
Dimensions.—Diameter of the rings 0.02, length of the outer spines 0.005.
Habitat.—Fossil in Guano from Peru and South Africa, also in Barbados.
11. Mesocena stellata, n. sp. (Pl. [101], fig. 9).
Rings circular, with sixteen teeth regularly disposed on the outer margin of the rings, eight stronger teeth alternating with eight smaller.
Dimensions.—Diameter of the rings 0.03, length of the larger spines 0.01.
Habitat.—Central area of the Pacific, Station 270, depth 2925 fathoms.