9. Phatnaspis quadratura, n. sp.
Parmal pores regular, square, all of nearly equal size and form, ten to twelve on each side of the primary diagonal rib, which arises from both edges of the compressed spines; two primary aspinal pores opposite on the two flat sides of the latter, not different from the other pores. Spines sword-like, their outer part about as long as the inner.
Dimensions.—Length of the shell 0.2, breadth 0.16; basal breadth of the spines 0.004.
Habitat.—Central Pacific, Station 274, surface.
10. Phatnaspis tabulata, Haeckel.
Parmal pores regular, circular, with square frames, all of nearly equal size, eight to ten on each side of the primary diagonal rib, which arises from both edges of the compressed spines; two primary aspinal pores opposite on the flat sides of the latter. Spines sword-like, short, scarcely half as long as the radius of the shell, their central ends are thickened and cause by their union the deceptive appearance of an enclosed "medullary shell."
Dimensions.—Length of the shell 0.12 to 0.15, breadth 0.1 to 0.12; breadth of the spines 0.006.
Habitat.—Mediterranean; Nice, Müller; Portofino, near Genoa, Haeckel, surface.
Subgenus 3. Phatnaspidium, Haeckel.
Definition.—In the centre of each rhomboidal plate four primary aspinal spines, forming a regular cross, the centre of which receives the cylindrical or four-sided prismatic spine.
11. Phatnaspis haliommidium, n. sp. (Pl. 136, fig. 7).
Parmal pores irregular quadrangular, of unequal size and form, eight to ten on each side of the crossed diagonal ribs, which arise at right angles from the four edges of the prismatic spines; four primary aspinal pores not different from the others. Outer part of the strong spines scarcely longer than the inner. (Resembling Icosaspis tabulata, Pl. 136, fig. 2, which, however, is distinguished by the spherical shell and the larger pores.)
Dimensions.—Length of the shell 0.22, breadth 0.17; breadth of the spines 0.016.
Habitat.—North Pacific, Station 244, surface.
12. Phatnaspis mülleri, n. sp.
Parmal pores regular, square, all of nearly equal size and form, twelve to sixteen on each side of the crossed diagonal ribs, which arise at right angles from the needle-shaped spines; the four
