REPORT ON THE RADIOLARIA. 1475 



in the sixth joint. Horn small, conical. This species differs from all others in the subregular 

 square form of the small pores. 



Dimensions. Length of the shell (with seven joints) 0'15 ; length of the seventh joint 0'024, 

 breadth 012. 



Habitat Central Pacific, Station 27l to 274, depth 2350 to 2750 fathoms. 



22. Lithostrobus hexagonalis, n. sp. (PI. 79, fig. 20). 



Shell broad, conical, smooth, with straight axis, and five to eight prominent girdles between six 

 and nine constricted broad joints. The first and the third joints are half as long as the second, the 

 fourth, and each of the following joints. The sixth joint is five times as broad as long. Pores sub- 

 regular, hexagonal, in regular transverse rows ; three to four rows in the first and the second joints, 

 six to eight in the third, the fourth, and each following joint. Cephalis with some small spines, 

 and a larger, oblique, curved horn. 



Dimensions. Length of the shell (with six joints) 0'2 ; length of the sixth joint 0'04, breadth 

 0-2. 



Habitat. Central Pacific, Station 272, depth 2600 fathoms. 



Subgenus 4. Botryostrobus, Haeckel. 



Definition. Shell conical, with straight axis, joints of different lengths. Cephalis 

 lobate, with some irregular constrictions. (Perhaps derived from Botryodea?). 



23. Lithostrobus botryocyrtis, n. sp. (PI. 79, figs. 18, 19). 



Shell slender, conical, smooth, with straight axis, and three deep strictures. Joints of different 

 lengths. The length of the fourth joint equals two-thirds of its breadth, and of the length of the 

 three preceding joints together. Each of the latter bears three transverse rows of small, quadrangular 

 pores, the fourth joint has six rows. The cephalis is irregularly lobate, with four to six prominent 

 lobes, and two small divergent horns (fig. 19). 



Dimensions. Length of the shell (with four joints) O'l ; length of the fourth joint 0'04, 

 breadth 0'06. 



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



24. Lithostrobus lithobotrys, n. sp. (PI. 79, fig. 17). 



Shell slender, conical, smooth, with straight axis, and four deep strictures. Joints of different 

 lengths, gradually increasing towards the mouth, the length of the fifth joint equals half its breadth, 

 and one-third of the length of the whole shell. The single joints bear each four or five transverse 

 rows of small, roundish pores. Cephalis irregularly lobate, with four to six prominent lobes, and 

 the same number of small, conical horns. 



