REPORT ON THE RADIOLARIA. 1651 



12. Challengeria havergalli, John Murray. 



Challengeria havergalli, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pi. A, 

 figs. 13, 13a. 



Shell subspherical, slightly compressed. Peristome semitubular, slender, somewhat curved, in 

 the lower half a simple half-cylinder, in the upper half forked, with two divergent teeth, nearly as 

 long as the shell. 



Dimensions. Diameter of the shell 01 to 015, length of the peristome 0'08 to 012. 



Habitat. South Pacific, Station 300, depth 1375 fathoms. 



13. Challengeria elephas, n. sp. 



Shell ellipsoidal, not compressed. Peristome very similar to that of Uhallengeron diodon 

 (PI. 99, fig. 6), from which this species differs mainly in the absence of an apical spine, and in a 

 more constricted mouth. The two conical teeth of the mouth are very large, nearly as long as the 

 shell, straight, and almost parallel, each tooth has a large hole on the thickened base. 



Dimensions. Diameter of the shell 0'22, length of the teeth 0'2. 



Habitat. Indian Ocean, Cocos Islands (Rabbe), surface. 



Subgenus 3. Challengerilla, Haeckel. 



Definition. Peristome with three teeth or trifid, with an odd dorsal and two paired 

 lateral teeth (Challengeria triodontes). 



14. Challengeria macleari, John Murray. 



Challengeria macleari, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pL A, 

 fig. 3. 



Shell subcircular, lenticular, with a sharp marginal edge. Peristome semitubular, an oblique 

 half-cylinder, with three divergent, short, triangular teeth ; the dorsal odd tooth nearly vertical, the 

 paired lateral teeth subhorizontal. Length of the peristome about one-third or one-fourth of the 

 diameter of the shell. 



Dimensions. Diameter of the shell 0'25 to 0'35, length of the peristome 01 to 012. 



Habitat. South Atlantic, Stations 325 to 332, depth 17.15 to 2900 fathoms. 



15. Challengeria tridens, n. sp. 



Shell subspherical, slightly compressed. Peristome about as long as the radius of the shell, with 

 three diverging and obliquely descending teeth ; the dorsal odd tooth twice as long as the paired 

 lateral teeth. 



Dimensions. Diameter of the shell - 08 to 012, length of the peristome - 05 to 0'07. 



Habitat. North Atlantic, Fseroe Channel (Gulf Stream), John Murray. 



