REPORT ON THE RADIOLARIA. 325 



equator. Medullary .shell ellip.soidal, nearly half a.s large a.s the cortical. Larger polar spine horn- 

 like curved, as long as the main axis, smaller scarcely half as long, pommel-shaped. 



Biftieriswns. — Major axis 009, minor 0'075 ; pores O'Ol, bars 0'003 ; axes of the medullary shell 

 0-04 and Q-QS ; length of the larger polar spine 0.06 to 0-09, of the smaller 0-04, basal breadth 0-02. 



Habitat. — Pacific, central area, Stations 270 to 272, surface. 



3. DrujJpcttractus helone, n. sp. 



Cortical shell thin walled, with smooth surface and regular network. Proportion of both axes 

 = 4:3. Pores circular, twice as broad as the bars ; ten to twelve on the half equator. Medullary 

 shell spherical, one-third as broad as the cortical shell. Polar spines strong, straight, cylindrical, 

 with conical apex, as broad at the base as two pores ; the larger once and a half to twice as 

 long as the main axis, the smaller only one-third to one-fourth as long. 



Bimensiotisi. — Major axis O'l to 0"12, minor 0-08 to 0'09 ; pores O'OOS, bars 0'004 ; diameter of 

 the medullary .shell 0-03 ; length of the larger polar spine 015 to 0"2, of the minor 0^04 to 0'05, 

 basal thickness of them 0'02. 



Hahitat. — Cosmopolitan ; Atlantic, Indian, and Pacific, surface. 



4. Druppatractus tcstuJo, Haeckel. 



Stijlosp/icera iestndo, Ehrenberg, 1872, Abhandl. d. k. AkaJ. d. Wiss. Berlin, p. 299, 

 Taf. viii. fig. 16. 



Cortical shell thick walled, spindle-shaped, with smooth surface and regular network. Propor- 

 tion of the two axes = 3 : 2. Pores circular, five times as broad as the bars; only six to seven on 

 the half equator. Medullary shell ellipsoidal, aliout one-third as large as the cortical shell. Polar 

 spines strong, short, three-sided p}-raniidal ; the larger as long as half the transverse axis, the 

 smaller only one-fourth as long. 



Dimensions. — Major axis 0-12, niinw- OvS ; pores 0-015, bars O'OOS ; axes of the medullary shell 

 0-04 and 0^03 ; length of the larger polar spine 0-04, of the smaller 0-02, basal thickness D'Ol. 



Hahitat. — Pacific, Philippine and Californian Sea (Ehrenberg), Stations 244, 266, 289, &c., depth 

 2550 to 2900 fathoms. 



Subgenus 2. Druppatractylis, Haeckel. 



Definition. — Network of the cortical shell regular or subregular, with meshes of 

 nearly equal size and similar form ; surface thorny or papillose, covered with small 

 conical spines or tubercles. 



5. Druppatractus accipenser, n. sp. 



(I'ortical shell thick walled, thorny, with regular network. Proportion of the two axes = 6:5. 

 Pores circular, each with a six-lobed outer opening, funnel-shaped, twice as broad as the bars ; nine 



