1048 THE VOYAGE OF H.M.S. CHALLENGER. 



4. Hexaspyris spinosa, Haeckel. 



Petalospyris spiiiosa, Stokr, 1880, Pal;eontogr., vol. xxvi. p. 98, Taf. iii. fig. 14. 



Shell subspherical, smooth, with slight sagittal stricture and irregular polygonal pores ; on 

 each side of the stricture two pairs of larger pores. Basal plate with two large pores only. 

 Apical horn short, pyramidal, three primary feet half as long as the shell and twice as long as the 

 three secondary feet. All six feet pyramidal, slightly divergent. 



Bime^isions.-^'&heW 0-05 long, 0-07 broad ; horn 0-02, feet 0-02 to 0-04 long. 



Habitat. — Fossil in Tertiary 'rocks of Sicily (Grotte, Caltanisetta). 



5. Hexasi^yi'is ophirensis, Haeckel. 



Petalospyris ophirensis, Ehrenberg, 1872, Abliandl. A', k. Akad. d. Wiss. Berlin, p. 297, Taf. ix. 

 fig. 24. 



Shell nut-shaped, with deep sagittal stricture and numerous irregular roundish pores ; two pairs 

 of larger pores on each side of the stricture. Apical horn short, curved. Six feet equal, 

 divergent, straight, slender, about as long as the shell. 



Dimensions. — Shell O^OS long, 01 broad; horn O'Ol, feet 0'05 to 0'08 long. 



Habitat. — Indian Ocean (Zanzibar), depth 2200 fathoms, PuUeu. 



Subgenus 2. Hexacorethra, Haeckel. 

 Definition. — Feet forked or branched. 



6. Hexaspyris hexacorethra, n. sp. (PL 95, fig. 8). 



Hexacorethra magica, Haeckel, 1882, Manuscript. 



Shell campanulate, smooth, with sharp sagittal stricture and irregular roundish pores. 

 Basal plate with six larger collar pores. Apical horn very long and thin, three-sided prismatic, 

 straight, ten to twenty times as long as the shell, branched at the distal end. Six feet thinner, 

 bristle-shaped, six to eight times as long as the sheH, divergent, irregularly curved, in the distal 

 part branched, besom-shaped ; the sternal foot at its base with a large conical horizontal spur. 



Dimensions. — Shell 0-034 diameter ; horn 04 to O'S long, feet 0'2 to 0'3 long. 



Habitat. — Central Pacific, Station 265, surface. 



7. Hexaspyris articulata, Haeckel. 



Ceratospyris articulata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xx. 

 fig. 4. 



Shell nut-shaped, tuberculate, with deep sagittal stricture and small irregular roundish pores. 

 Basal plate with six pores (?). Apical horn conical, longer than the shell. Six feet very large, thick 



