344 THE VOYAGE OF H.M.S. CHALLENGEE. 



Dimensions. Length of the shell - 24, breadth 0'05. 



Habitat. Pacific, central area, Station 268, depth 2600 fathoms; fossil in the Tertiary rocks of 

 Sicily, Stohr. 



Subgenus 2. Spongurella, Haeckel. 



Definition. Spongy framework everywhere of the same structure ; surface armed 

 with radial spines. 



4. Spongurus asper, Haeckel. 



Haliomma asperum, Job.. Muller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 40, Taf. ii. 



fig. 2. 

 Haliomma asperum, Haeckel, 1862, Monogr. d. Eadiol., p. 431. 



Shell ellipsoidal, one and a third times as long as broad, with thorny surface and twenty 

 symmetrically disposed, thin, bristle-shaped, radial spines, about as long as the shell. Spongy 

 framework everywhere of the same structure, very compact, with small meshes, three to four tunes 

 as broad as the bars. 



Dimensions. Length of the shell O'll, breadth 0'08. 



Habitat. Mediterranean, Ligurian coast (J. Muller), Portofino (Haeckel). 



5. Spongurus cylindricus, Haeckel. 



Sponr/urus cylindricus, Haeckel, 1862, Monogr. d. Radiol., p. 465, Taf. xxvii. fig. 1. 



Shell cylindrical, four to five times as long as broad, with nearly smooth surface, and twenty to 

 thirty thin, bristle-shaped, radial spines, about half as long as the shell. Spongy framework every- 

 where of the same structure, very compact, with small meshes, scarcely broader than the bars. 



Dimensions. Length of the shell 0'2, breadth 0'04 to 0'05. 



Habitat. Cosmopolitan ; Mediterranean, Atlantic, and Pacific, surface. 



6. Spongurus tricolus, n. sp. 



Shell nearly cylindrical, with two slight annular transverse strictures ; its middle part is 

 somewhat broader. Surface thorny, with numerous (forty to sixty or more) short, thin, radial 

 spines, not longer than the breadth of the shell. Spongy framework everywhere of the same 

 structure, compact, with small meshes, twice to three times as broad as the bars. 



Dimensions. Length of the shell 0'24, breadth 0'04 to 0'06. 



Habitat. Pacific, central area, Station 272, 2600 fathoms. 



Subgenus 3. Sponguroma, Haeckel. 



Definition. Spongy framework in the inner part of the shell very compact, in the 

 outer part very loose ; surface armed with radial spines. 



