REPORT ON THE RADIOLARIA. 1689 



1. Castanura tizardi, n. sp. (PI. 113, fig. 4, 4a). 



Pores regular, circular, without hexagonal frames, twice as broad as the bars. Bristles twice as 

 long as one pore. Eadial main-spines somewhat longer than the radius, straight, very stout, with 

 irregular lateral branches, which are partly confluent. Mouth with six strong conical teeth. 



Dimensions. Diameter of the shell - 6, of the pores 0'03. 



Habitat. Tropical Atlantic, Station 346, surface. 



2. Castanura havergali, n. sp. 



Pores regular, circular, hexagonally framed, as broad as the bars. Bristles three times as long 

 as one pore. Radial main-spines as long as the shell-diameter, in the basal half simple, in the 

 distal half with irregular, not confluent, lateral branches. Mouth with ten to twelve irregular, 

 parallel, conical teeth of different sizes. 



Dimensions. Diameter of the shell 0'5, of the pores 0'045. 



Habitat. Indian Ocean, Madagascar (Eabbe), surface. 



3. Castanura sivirei, n. sp. 



Pores regular, circular, hexagonally framed, as broad as the bars. Bristles half as long as the 

 radius. Eadial main-spines straight, longer than the shell-diameter ; on the distal end with a few 

 irregular, confluent, lateral branches. Mouth with six larger and six alternate smaller, parallel, 

 conical teeth. 



Dimensions. Diameter of the shell 0'2S, of the pores 0'015. 



Habitat. North Pacific, Station 253, surface. 



4. Castanura carpcnteri, n. sp. 



Pores irregular, roundish, twice to four times as broad as the bars. Bristles about as long as the 

 largest pores. Eadial main-spines irregularly curved, longer than the shell-diameter, with inflated 

 and fenestrated conical base ; in the distal half irregularly branched, with simple, not confluent, 

 lateral branches. Mouth with six to nine irregular, strong, conical teeth. 



Dimensions. Diameter of the shell 0'3, of the pores 0'012 to - 025. 



Habitat. South Atlantic, Station 331, depth 1715 fathoms. 



Family LXXXI. CIKCOPORIDA, Haeckel, 1879 (Pis. 114-117). 



Circoporida, Haeckel, 1879, Sitzungab. med.-nat. Gesellsch. Jena, Dec. 12, p. 5. 



Definition. PH^ODARIA with a spherical or polyhedral shell, exhibiting a 

 peculiar solid porcellanous structure, with, a stellate circle of radial pores around the 

 base of the hollow radial spines. Mouth usually with teeth. Surface of the shell 



(ZCOL. CHALL. EXP. PART XL. 1886.) Rr 212 



