REPORT ON THE RADIOLARIA. 395 



6. Ommatocampe chcetopodinn , n. sp. 



Cortical shell with spiny surface, composed of six (or more) kidney-shaped chambers of different 

 size and foi-m. Both proximal chambers kidney-shaped, with subregular, circular, hexagonally 

 framed pores, about as broad as the bars. All the following chambers hemispherical, with irregular, 

 roundish pores ; at the base of every chamber a circle of ten to twelve larger square pores. The 

 beams between these latter are prolonged into free radial spines, twice as thick as the bars. Therefore 

 every chamber is surrounded by a circle of radial spines, like those of Panicium coronatum (PI. 40, 

 fig. 4). Both medullary shells lenticular. 



Dimensions. — Length of the six-chambered cortical shell 0-3, greatest breadth 0'08 ; pores and 

 bars of both proximal chambers O'Ol ; pores of the other chambers 0-00'2 to 0-008 ; square pores 0'02, 

 bars O^OOS ; length of the coronal spines 0'0.3, thickness O'Ol. 



Habitat. — Indian Ocean, Madagascar, Eabbe. 



Subgenus 4. Omviatacantha, Haeckel. 



Definition. — Surface of the shell smooth or spiuy, on the poles of the main axis 

 occur two strong opposite polar spines. 



7. Ommatocampe amphilonche, n. sp. 



Cortical shell composed of six kidney-shaped chambers of nearly the same size and structure ; 

 every chamber twice as broad as long, with four to five transverse rows of irregular, roundish poi'es, 

 once to four times as broad as the bars. Both medullary shells lenticular. Surface of the cortical 

 shell covered with bristle-like spines. On both poles of the main axis one larger, strong, conical 

 spine, about half as long as this axis, and on the base as broad as the inner medullary shell. 

 (Eesembles on the whole Dcsmartjis Inrvalis, PI. 40, fig. 12, but without external mantle, and 

 with two sohd polar spines instead of the polar tubes.) 



Dimensions. — Length of the six-chambered cortical shell 0'24 ; greatest breadth of each chamber 

 0-08; pores 0-002 to 008, bars 0-002 ; length of the polar spines 0-12, basal thickness 0-02. 



Habitat. — Pacific, central area. Station 266, depth 2750 fathoms. 



Genus 170. Ommatartus,^ Haeckel, 1881, Prodromus, p. 463. 



Definition. — Z y g a r t i d a vi^ith simple cortical shell and double meduUary shell, 

 with tw-o hollow fenestrated tubes, opposite on both poles of the main axis. 



The genus Ommatartus differs from Ommatocampe by the development of two 

 hoUow fenestrated tubes on both poles of the main axis, and bears therefore the same 

 relation to it as Cannartidium to Cyphonium. The former two genera differ from 

 the two latter by the augmentation of the chambers of the cortical shell. 



' Ommatart-us = Loaf with eyes ; d"«jk«, ajrof. 



