REPORT ON THE RADIOLARIA. 211 



5. Acanthosphcera dentata, HaeckeL 



Cladococeus dentatus, Haeckel, 1862, Monogr. d. Radioi, p. 367, Taf. xiii. fig. 10. 



Shell thin walled, eight to ten times as broad as one pore. Pores regular, circular, hexa- 

 gonally framed, three times as broad as the bars. Radial spines arising from all the nodal-points of 

 the network, three-sided prismatic, with dentated or serrated edges, longer than the shell diameter. 



Dimensions. Diameter of the shell 0'08, pores O'Ol, bars 0'003 ; length of the spines O'l, 

 breadth 0'003. 



Habitat. Mediterranean (Messina), surface. 



6. Acanthosphcera acufera, Haeckel. 



Rhaphidococcus acufer, Haeckel, 1862, Monogr. d. Radioi., p. 366, Taf. xiv. fig. 1. 

 Cladococeus acufer, Haeckel, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 800. 



Shell thiii walled, eight to ten times as broad as one mesh. Pores regular, circular, three 

 times as broad as the bars. Radial spines bristle-shaped, arising with thicker conical bases from all 

 the nodal-points, about as long as the diameter of the shell. 



Dimensions. Diameter of the shell O08, pores O'Ol, bars O'OOS ; length of the spines 0'08. 



Habitat. Mediterranean (Messina); North Atlantic, Station 354, surface. 



7. Acanthosphcera castanea, n. sp. (PI. 26, fig. 3). 



Shell thick walled, thirty times as broad as one mesh. Pores regular, circular, nearly of the 

 same breadth as the bars. Radial spines bristle-shaped, arising with thicker conical bases from all 

 the nodal-points, scarcely half as long as the radius of the shell. 



Dimensions. Diameter of the shell 0'15, pores and bars 0'005 ; length of the spines 0'03. 



Habitat. North Pacific, Station 244, surface. 



8. Acanthosphcera flosculenta, n. sp. 



Shell thick walled, thirteen times as broad as one mesh. Pores regular, circular, three times as 

 broad as the bars, with an elegant six-lobed frame (PL 28, fig. 1&). In the intervals between the 

 six lobes of each mesh arise six conical radial spines (half as long as the radius), six around each 

 pore. (Differs from the similar Haliomma flosculentum, PI. 28, fig. 1, in the absence of an enclosed 

 medullary shell and the stronger development of the spines.) 



Dimensions. Diameter of the shell 0'13, pores O'Ol, bars 0'003 ; length of the spines 0'03. 



Habitat. Indian Ocean, Cocos Islands, surface, Rabbe. 



Subgenus 2. Rhaphidocapsa, Haeckel. 



Definition. Pores of the spherical shell regular or subregular, all of nearly equal 

 size and similar form. Eadial spines scattered at some distance apart, not at all the 

 nodal -points. 



