Shell very thin walled, with smooth surface, without crest and dimples. All pores of nearly equal size and form; quadrangular, mostly rectangular; one hundred to two hundred, separated by two systems of parallel bars, perpendicular one to another, occur in each plate. Sutural pores mostly triangular. Radial spines very thin and long, cylindrical, somewhat compressed. (Similar to those of Phatnaspis lacunaria, Pl. [136], fig. 9, but spherical, not ellipsoidal.)
Dimensions.—Diameter of the shell 0.2, pores 0.008 to 0.012.
Habitat.—Central Pacific, Station 272, surface.
7. Coscinaspis parmipora, n. sp. (Pl. [137], fig. 9).
Craniaspis parmipora, Haeckel, 1866, Manuscript.
Dorataspis parmipora, Haeckel, 1881, Prodromus, Atlas.
Shell thin walled, with smooth surface, without crests and dimples. There are no sutural pores, since all twenty plates are connected by perfect sinuate sutures (therefore this excellent species may perhaps better represent a peculiar genus, called by me in 1866 Craniaspis). All pores are parmal pores; each plate with two elliptical aspinal pores, which are twice to five times broader than the numerous, roundish irregularly scattered coronal pores (thirty to fifty occurring on each plate). The radial spines are quite internal, that is, not prolonged on the outside of the shell; in this respect they resemble those of Sphærocapsa.
Dimensions.—Diameter of the shell 0.16, aspinal pores 0.01, coronal pores 0.002 to 0.005.
Habitat.—North Atlantic, Canary Islands (Lanzerote), surface.
8. Coscinaspis isopora, n. sp. (Pl. [134], figs. 13, 14).