REPORT ON THE RADIOLARIA. 43 7 



Dimmsions. — iJiameter of the disk 0-2, of the mechilbrv shell 0-0.', ; lenoth of the spines 0-05 

 basal breadth 0-04. 



Habitat. — Central Pacific, Station 265, depth 2900 fathoms. 



2. Distriactis coixillant/ia, u. sp. 



Disk thorny, three tuiaes as broad as the medullary shell, with regular, circular pores, about 

 eight on the radius. Six marginal spines of equal size and equidistant, conical, nearly as long as the 

 diameter of the disk, half as broad at the l)ase as the medullary shell. 



Dimensions. — Diameter of the disk 0-12, of the medullary shell 0-04; length of the spines Ol 

 breadth 0-02. 



Habitat.— '^ionth Pacific, Station 300, surface. 



3. Distriactis alterna, n. sp. 



Disk smooth, five times as broad as the medullary shell, about twelve pores on the radius. Six 

 marginal spines pyramidal, at equal distances, but unequal alternating size ; three larger (perradial) 

 spines as long as the shell radius, three smaller between them (interradial) half as long and broad. 



Binunsions. — Diameter of the disk O'I.t, of the medullary shell 0-il'^; length of the three major 

 spines 0'08, of the three minor 0"05. 



Habitat. — North Atlantic, Station ijo."!, surface. 



4. Di.striactis palmantltn, n. sp. 



Disk rough, four times as broad as the medullary shell, about ten pores on the radius. Six 

 marginal spines conical, at equal distances, but unequal alternating size ; three larger (perradial) 

 spines as long as the shell diameter, three smaller between them (interradial) as long as the radius. 



Dimensions. — Diameter of the disk 0"2, of the medullary shell O'Oo ; length of the three major 

 spines 0'2, of the three minor 01. 



Habitat. — South Atlantic, Station '525, surface. 



5. Di.^triactis ampkithecta, u. sp. 



Disk thorny, three tunes as broad as the medullary shell. Six marginal spines conical, of very 

 different size ; one single (anterior) much larger than tlie five others, the opposite (posterior) much 

 smaller. The other four spines are paired, the anterior pair larger than the posterior. 



Dimensions. — Diameter of the disk 0'15, of the medullary shell 0"05 ; length of tlie longest 

 spine 0"2, of the shortest 0'04, of the anterior pair O'l, of the posterior 0-07. 



Habitat. — Indian Ocean, Cocos Islands, surface, Eabbe. 



