REPORT ON THE RADIOLARIA. 137 



13. Stylosphcera jugata, n. sp. 



Radial proportion of the two shells = 2:1. Cortical shell thick walled, smooth, with irregular, 

 roundish, double-contoured pores, confluent in groups of two to six. On the half equator six to 

 nine groups and fifteen to twenty pores ; bars between them of very variable breadth. Polar spines 

 very strong, three-sided pyramidal, twice as long as the axis of the outer sphere, half as broad at the 

 base as its radius. (Nearly allied to Lithatractus jugatus, PI. 16, fig. 2, but differs in the truly 

 spherical form of both shells and the double length of the polar spines.) 



Dimensions. Diameter of the outer shell 015, pores 0'005 to O002 ; inner shell 0'07 ; length 

 of the polar spines - 25 to 0'3, basal breadth 0'03. 



Habitat. Western Tropical Pacific, Station 224, depth 1850 fathoms. 



14. Stylosphcera terpsichore, n. sp. 



Eadial proportion of the two shells = 3:1 or 4 : 1. Cortical shell thick walled, smooth, with 

 irregular, roundish pores, one to three times as broad as the bars ; fifteen to twenty-five on the half 

 equator. Polar spines conical, about as long as the axis of the outer sphere, as broad at the base 

 as the inner shell 



Dimensions. Diameter of the outer shell 015 to 0'2, pores 0'005 to 0'02, bars 0'004 to O'OOS ; 

 inner shell 0'05 ; length of the polar spines 015 to 0'25, basal breadth 0'05. 



Habitat. Western Indian Ocean, Zanzibar, depth 2200 fathoms, Pullen. 



Subgenus 4. Stylosphceromma, Haeckel. 



Definition. Pores of the cortical shell irregular, of different size or form ; surface 

 spiny or thorny. 



15. Stylosphcera thalia, n. sp. 



Radial proportion of the two shells = 2:1. Cortical shell thin walled, thorny, with irregular, 

 roundish pores, two to four times as broad as the bars ; eight to twelve on the half equator. Polar 

 spines conical, one to one and a half times as long as the axis of the outer sphere, one-fourth to one- 

 sixth as thick at the base. (Resembles Sph&rostylw ophidium, PL 16, fig. 14, but differs in the 

 straight regular conical polar spines, both of equal length and similar form.) 



Dimensions. Diameter of the outer shell 012, pores O'Ol to 0'02, bars 0'005 ; inner shell 0'06 ; 

 polar spines 01 to 016 long, 0'03 broad. 



Habitat. South Pacific, Station 302, depth 1450 fathoms. 



16. Stylosphcera erato, n. sp. 



Radial proportion of the two shells = 3:l. Cortical shell thick walled, thorny, with irregular, 

 roundish pores, two to five times as broad as the bars ; fourteen to eighteen on the half equator. 

 (ZOOL. CIIALL. EXP. PAET XL. 1885.) Er 1 8 



