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



3. Solenosphcera megalactis, Haeckel. 



Trisolenia megalactis, Ehrenberg, 1872, AbhandL d. k. Akad. d. Wiss. Berlin, p. 301, Taf. via. 

 fig. 19. 



Shell irregularly polyhedrical, with very small roundish pores, scarcely half as broad as the bars. 

 Only eight to ten pores on the half meridian of the shell. Porous, tubuli of the shell of variable 

 number (in one and the same colony), two to five, mostly three or four ; cylindrical, about as long 

 as the radius of the shell. Inner aperture of the tubuli commonly as broad as the half radius of 

 the shell, and quite as broad as the truncated outer aperture. 



Dimensions. Diameter of the shell 0'07 to 0'09, of the pores 0'002 to 0004, of the bars 

 0'005 to 0-009 ; length of the tubuli 0'03 to 0'04, breadth of them 0'02. 



Habitat. Pacific ; California, Philippine Sea, Ehrenberg ; Stations 256 to 285, depths 310 

 to 3000 fathoms. 



4. Solenosphcera ~serpentina, n. sp. (PI. 7, fig. 7). 



Shell nearly spherical, with very small circular pores, scarcely one-third or one-fourth as broad 

 as the bars. Only five to seven pores in the half meridian of the shell. Porous tubuli of the shell 

 of variable number (in one and the same colony), two to nine, mostly seven or eight ; cylindrical, 

 somewhat curved or contorted, once and a half or twice as long as the diameter of the shell, with 

 few very small and widely scattered pores. Inner and outer aperture of the tubuli have the same 

 diameter, about one-fifth or one-fourth that of the shell. (This species is closely allied to Siphono- 

 sphcera serpula, but is distinguished from it by the long tortuous tubuli and the small scarce pores.) 



Dimensions. Diameter of the shell 0'08 to 01, of the pores O'OOl to 0'002, of the bars 

 0-004 to 0-008 ; length of the tubuli 012 to 018, breadth of them 0'02 to 0'025. 



Habitat. North-eastern Pacific, between Sandwich Islands and California, Haltermann, surface. 



Subgenus 2. Solenosphenia, Haeckel. 



Definition. Tubuli of the shell more or less conical, the inner aperture much 

 larger than the outer aperture. 



5. Solenosphcera venosa, Haeckel. 



Tetrasolenia venosa, Ehrenberg, 1872, AbhandL d. k. Akad. d. "VViss. Berlin, p. 301, Taf. vii. 

 fig. 22. 



Shell irregular polyhedral or roundish, with a delicate network of large irregular polyhedral meshes, 

 five to ten times as broad as the thin bars. Eight to twelve meshes on the half meridian of the 

 shell. Fenestrated tubuli of the shell of variable number (in one and the same colony), one to 

 five, commonly three or four, shaped like a short truncated cone, about half as long as broad on its 

 base, shorter than the radius of the shell. Inner aperture of the cone nearly as broad as the half 

 radius of the shell, about twice as broad as the truncated outer aperture. 



