REPORT ON THE RADIOLARIA. 237 



23. Haliomma spinulosum, J. Mtiller. 



Haliomma sjnnulusum, J. Miiller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 39, Taf. iv. 

 fig. 6. 



Cortical sheU thin walled, twice as broad as the medullary shell, with irregular, polygonal pores, 

 and very thin bars. Pores of the inner shell subregular, hexagonal, ten to twelve times as broad as 

 the bars. Eadial spines very numerous, bristle-shaped, one-sixth to one-fourth as long as the 

 radius of the outer shell. 



Dimensions. — Diameter of the outer shell OIG, inner 0'08 ; outer pores O'Ol to 0'03, inner 0'02 ; 

 length of the spines 0-02 to 0-03. 



Habitat. — Mediterranean (Nice) ; Central Pacific, Station 266, surface. 



24. Haliomma rliodococcus, n. sp. (PI. 19, fig. (">). 



Sethospliaera rliodococcus, Haeckel, 1879, Atlas, pi. xix. fig. 6. 



Cortical shell very thin walled, little larger than the thick walled medullary shell (=10:9). Pores 

 of the outer shell very irregular, roundish, twice to six times as broad as the bars, about twenty on 

 the radius. Pores of the inner shell twice as broad as the bars, six to eight on the radius, very 

 regular, circular on the inner, six-lobed on the outer opening, separated by prominent hexagonal 

 crests ; in the hexagon-corners arise short conical radial spines, which at equal distances from 

 the centre are united by the outer shell, but are prominent over its surface. (A very peculiar 

 form ; the two shells may better be regarded as inner and outer cortical shell.) 



Dimensions. — Diameter of the outer shell 0'2, inner 0'18 ; outer pores 0'04 to 0'012, inner O'Ol ; 

 length of the spines O'Ol. 



Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms; also fossil in Barbados. 



25. Haliomma horeale, n. sp. 



Cortical shell thick walled, four times as broad as the medullary shell, with u-regular, roundish 

 pores, twice to four times as broad as the bars ; eight to ten on the radius. Pores of the inner shell 

 regular, circular, twice as broad as the bars, four to six on the radius. Eadial spines very numerous, 

 conical, nearly as long as the diameter of the shell. 



Dimensions. — Diameter of the outer shell 0'24, inner 006 ; outer pores 0'008 to 0'02, bars 

 0'005, inner pores 0'006, bars 0'003 ; length of the spines 0'2. 



Habitat. — Arctic Ocean, Greenland (" Alert " Expedition). 



Subgenus 4. Haliommura, Haeckel. 



Definition. — Pore.s of the cortical shell irregular, of different size and form ; spines 

 not covering the entire surface, but scattered at intervals (their number smaller than 

 that of the nodal-points m the network). 



