REPORT ON THE RADIOLARIA. 83 



1. Rhodosphcera hexagonia, n. sp. 



Both cortical shells with the same number of regular hexagonal pores ; the inner four times as 

 broad as the bars, and half as broad as the outer pores, which are separated by thread-like bars. 

 Medullary shell only one-fourth as broad as the inner cortical shell, with regular hexagonal pores 

 of half the size. (Differs from the similar Liosphcera hexagonia, PI. 20, fig. 3, by the possession of 

 a medullary shell.) 



Dimensions. Diameter of the outer shell 0'2, middle 016, inner 0'04 ; Outer pores 0'013, 

 middle O'OOS, inner 0004. 



Habitat. Central Pacific, Station 266, depth 2750 fathoms. 



2. Rhodosphcera melitomma, n. sp. 



Both cortical shells with the same number of regular pores ; the inner regular, circular, twice 

 as broad as the bars, with elegant hexagonal frames and six roundish lobes alternating with the six 

 radial spines which arise from the hexagon-corners ; these short conical spines are connected at 

 the distal end (at equal distances from the centre) by delicate threads (three from each spine), 

 which form the delicate external shell. Medullary shell one-third as broad as the inner 

 cortical shell, with small, simple, regular circular pores. (If in Carposphwra melitomma, PI. 20, 

 fig. 4, the distal ends of the spines became united by a cobweb-like outer shell, this species 

 would be formed.) 



Dimensions. Diameter of the outer shell 0'22, middle 0'18, inner 0'06; outer pores 0'025, 

 middle 0'0125, inner 0'005. 



Habitat. Central Pacific, Station 270, depth 2925 fathoms. 



Subgenus 2. Rhodosphceromma, Haeckel. 



Definition. Pores of both cortical shells irregular, in each shell of unequal size or 

 dissimilar form. 



3. Rhodosphcera palliata, n. sp. 



Both cortical shells with an unequal number of irregular roundish pores ; the outer pores somewhat 

 smaller and much more numerous than the inner pores ; the bars between the latter are thicker. 

 Medullary shell about one quarter as broad as the inner cortical shell, with regular circular pores. 



Dimensions. Diameter of the outer shell 0'4, middle - 36, inner 0'08 ; outer pores on an 

 average O'OOS, middle 0'012, inner 0'004. 



Habitat. Fossil in Barbados. 



4. Rhodosphcera pentaphylla, n. sp. 



Both cortical shells with unequal number of irregular roundish pores ; the inner pores large, 

 three to four times as broad as the bars ; to each inner pore corresponds a group of five smaller 



