2. Spirema melonia, n. sp. (Pl. [49], fig. 1).
Cortical shell nearly spherical, with smooth surface; proportion of its three dimensive axes = 1.4 : 1.5 : 1.6. In the median plane are visible three perfect turnings of the simple spiral, all of the same breadth as the simple spherical medullary shell; the breadth of each convolution somewhat greater at the poles of the principal than at the poles of the sagittal axis.
Dimensions.—Length of the shell 0.16, breadth 0.15, height 0.14; medullary shell 0.018.
Habitat.—Pacific, central area, Station 271, surface.
3. Spirema flustrella, Haeckel.
Flustrella haliomma, Ehrenberg (1861), Abhandl. d. k. Akad. d. Wiss. Berlin, 1872, p. 293, Taf. ii. fig. 6.
Cortical shell egg-shaped, with thorny surface; proportion of its three axes = 4 : 5 : 6. In the median plane are visible three perfect turnings of the simple spiral, the first and second of about the same breadth as the simple spherical medullary shell, the third suddenly increasing, and finally three to four times as broad. Network of the surface irregular, with roundish pores.
Dimensions.—Length of the shell 0.2, breadth 0.17, height 0.14; medullary shell 0.013.
Habitat.—North Atlantic, Greenland, 1000 fathoms, Ehrenberg; Færöe Channel, John Murray.