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



species is similar to Frripanai-tus atradus, PI. 40, iig. 7, but is without the superficial spines ami tlie 

 equatorial girdle-like envelope of the latter.) 



Dimensions. — Total length of the shell 0"2.5 to 0'3 ; greatest breadth (in the equator of the 

 proximal chambers) 0'08 to O'Ol ; pores of the proximal chambers 0-008 to 0'012, pores of the distal 

 chambers half their size, bars 0'002 to 0-006. 



HaMtat. — North Pacific, Station 237, surface. 



9. Panartus profundissimus, Haeckel. 



Ommatocampe profundissima, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 297, 

 Taf. viii. fig. 6. 



Both proximal chambers nearly ellipsoidal, with irregular, polygonal pores, six to eight times as 

 broad as the bars ; four to five pores on the half meridian, eight to nine on the half equator of eacli 

 chamber. Both distal chambers hemispherical, with a very delicate irregular network. Medullary 

 shells spherical ; surface of the shell smooth. 



Dimensions. — Total length of the shell 0'15 ; greatest hreadtli in tlie equator of the proximal 

 cliambers 0'08 ; pores of the proximal chambers 0'15, bars 0'002. 



Habitat. — Philippine Sea, deptli 3300 fathoms, Ehrenberg; Station 213, depth 2050 fathoms. 



Subgenus 3. Panartoma, Haeckel. 



Definition. — Surface of the cortical shell thorny, covered with scattered .spines. 

 All its four chambers exhibit the same form and structure. 



10. Panartus quadriceps, n. sj). 



All four chambers of the cortical shell of the same form, size, and structure, kidney-shaped, 

 twice as broad as long. Pores rather regular, circular, with hexagonal frames, twice to three times as 

 broad as the bars ; six to seven pores on tlie half meridian, ten to twelve on the half equator of 

 each chamber. Surface spiny ; from the corners of tlie hexagonal frames (between every three 

 pores) arise short radial spines. Both medullary shells sphei'ical, the outer one-third as broad as the 

 constriction of the cortical shell. (All the four chambers of this species have the same form as 

 the two proximal chambers of PeripoMartus avvphicanus, PL 40, fig. 5.) 



Dimemions. — Main axis of the cortical shell 0'24, equatorial axis O'OS ; meshes O'Ol, bars 0'003 

 to 0-005 ; length of the spines O'Ol to 0-02. 



Habitat. — Pacific, central area. Station 274, depth 2750 fathoms. 



11. Panartus quadrijugus, n. sp. 



All four chambers of the cortical shell of the same form and size, kidney-shaped, twice as 

 broad as long. Pores irregular, roundish, twice to three times as liroad as the bars ; a circle of 

 larger pores at the base of both distal chambers ; six to eight pores on the half meridian, twelve to 



