154 THE VOYAGE OF H.M.S. CHALLENGER. 



6. StaurosphcBra jacohi, n. sp. 



Shell thick walled, smooth, with regular, circular pores, twice as hroad as the bars ; eleven to 

 twelve on the quadrant. Four spines cylindrical, three times as long as the radius, three times as 

 broad as one mesh. 



Dimensions. — Diameter of the shell 01, pores O^OOG, bars 0'003. 



Habitat. — North Atlantic, Station 353, depth 2965 fathoms. 



7. StaurosplioBra simonis, n. sp. 



Huliomma with four spines, Bury, 1862, Polycystins of Barbados, pi. iv. fig. 4. 



Shell thick walled, smooth, with regular, circular pores, of the same breadth as the bars ; eight to 

 ten on the quadrant. Four spines cylindrical, twice as long as the radius, five times as broad as 

 one mesh. 



Dimensions. — Diameter of the sphere O'l, pores and bars 0'003. 



Habitat. — Fossil in Barbados. 



Subgenus 2. Staurosphcerella, Haeckel. 



Definition. — Pores regular, all of nearly equal size and similar form ; surface covered 

 with by-spines or accessory thorns. 



8. Staurosphcera philippi, n. sp. (PL 15, fig. 6). 



Shell thin walled, covered with bristle-shaped by-spines, as long as the radius. Pores regular, 

 circular, twice as broad as the bars ; six to eight on the quadrant. Four main spines cylindrical, 

 five to ten times as long as the radius, as broad as one mesh. 



Dimensions. — Diameter of the shell 0'08, pores 0006, bars 0003. 



Habitat. — Central Pacific, Station 272, surface. 



9. Staurosphcera andrece, n. sj). 



Shell thick walled, with regular, circular, he.xagonally fi'amed pores, three times as broad as the 

 bars ; nine to ten on the quadrant. From each hexagon-corner arises a bristle-shaped by-spine, half 

 as long as the radius. Four main spines three-sided pyramidal, with spirally contorted edges, as long 

 as the radius (very similar to Hcxastylus solonis, PI. 21, fig. 11, but with only four spines). 



Dimensions. — Diameter of the shell 0'16, pores 001, bars 0'003. 



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



