REPORT ON THE RADIOLARIA. 1485 



5. Lithomitra eruca, n. sp. (PI. 79, fig. 3). 



Shell subcylindrical, diminishing slightly towards both ends, with ten to fifteen slight strictures. 

 On each joint a single transverse row of circular pores, descending obliquely in the wall. The two 

 or three first joints form together a roundish cephalis. Usually each joint is three times as broad 

 as long. 



Dimensions. Length of the shell (with twelve joints) 0'2 ; length of each joint (on an average) 

 0-016, breadth 0'05. 



Habitat. Central Pacific, Station 265 to 268, depth 2700 to 2900 fathoms; fossil in Barbados. 



6. Lithomitra chrysalis, n. sp. (PI. 79, fig. 4). 



Shell subcylindrical, diminishing slightly towards both ends, with elegant longitudinal ribs, and 

 with five to eight slight strictures. Each of the upper joints with two (or sometimes three) trans- 

 verse rows of small pores ; each of the lower joints with only a single row. 



Dimensions. Length of the shell (with six joints) Oil ; length of each joint O'Ol to 0'015, 

 breadth 0'04 to 0'05. 



Habitat. Central Pacific, Station 266, depth 2750 fathoms. 



Subgenus 2. Lithomitrissa, Haeckel. 



Definition. All (or the majority) of the joints of the shell with several trauverse 

 rows of pores, in variable number. 



7. Lithomitra cylindrica, n. sp. 



Shell cylindrical, smooth, with twelve to sixteen internal septal rings (without external stric- 

 tures). On each joint two transverse rows of small, regular, circular pores. The hemispherical 

 cephalis also has two rows of pores. Each joint is twice as broad as long. 



Dimensions. Length of the shell (with sixteen joints) 0'3; length of each joint - 02, breadth 

 0-04. 



Habitat. South Pacific, Station 297, depth 1775 fathoms. 



8. Lithomitra costata, Haeckel. 



Dictijomitra costata, Stohr, 1880, Palaeontogr., vol. xxvi. p. 101, Taf. iii. fig. 23. 



Shell with longitudinal ribs, in the upper half conical, in the lower half cylindrical, with six to 

 eight slight strictures. Small, circular pores in regular transverse rows ; three rows in each upper 

 joint, two rows in each lower joint (the last joints sometimes confluent). 



