30 P. T. CLEVE. PLANKTON COLLECTED BY THE SWEDISH EXPEDITION TO SPITZBERGEN. 



Hexadoras borealis Cl. N. sp. 



Primordial shell: irregularly spherical, 0,03 to 0, 04 mm. in diameter, with irregular, 

 rourided or polygonal pores, 2 to 3 on the radius, and thin bars. Spines six, excep- 

 tionally more, strong, with triangulär apophyses in the raiddle. Pl. II, tig. 4 a. 



Oiiter shell: a rounded or octahedric, more or less intricate net-work of anastomos- 

 ing, silicious threads, issuing from the proximal edges of the spines. Spines usually six 

 (rarely as in Rhizoplegma 8 to 10) strong, three-sided slightly spirally twisted, with 

 elegantly aculeate, winged edges. 



Diam. 0, 12 to 0,16 mm. Spines 0,i mm. Pl. II, fig. 4 b, c. 



Deep-sea hauls: 



Date. 



Lat, N. 



Long. 



Depth. 



Fq. 



Pl. 



1 VIII 



76° 36' 



12° 18' E. 



500-0 m. 



r 



TS 



27 VIII 



79° 58' 



9°35'E. 



400-0 » 



v 



Cä 



5 IX 



71° .50' 



19° 2'E. 



230—0 » 



v 



S 



Habitat: North Atlantic, between Shetlands and Norway, surface, March 1898 (Cl.). 



Litholoplius liguriniis Hkl. (Z. arcticus Aueiv.). 

 Surface : 



Beep-sea hauls: 



Date. 



Lat. N. 



LoBg. 



Temp, 



Sal. 



Fq. 



Pl. 



26 VII 



78° 13' 



7°30' E. 



5,.B4 



34,89 



r 





27 VIII 



79° 58' 



9°35' E. 



4,58 



34,53 



r 



T 



39 VIII 



77° 23' 



10=53' E, 



5,55 



35,03 



v 



S T 



31 VIII 



76° 27' 



10° 43' E. 



5,35 



35,03 



r 



S 



31 VIII 



76° 12' 



12°18'E. 



6,26 



35,15 



r 



ti 



Date. 



Lat. N. 



Long. 



Depth. 



Fq. 



Pl. 



36—27 VII 

 27 VIII 



77° 39' 

 79° 58' 



ri8'E. 

 9°35'E. 



100-0 ra. 

 400-0 . 



+ 

 r 



cs 



Habitat: Mediterranean, central Pacific Ocean (Hkl.). 



Lithomitra aiistralis (Ehb.)? The shell Pl. II, fig. 5 seems to be the upper joints 

 of Eucyrtidium australe Ehb. from the South Polar ice (Microg. 35 A XXI, f. 18). It was 

 found very rarely in the haul 29—30 VII. Lat. N. 78° 13'. Long. W. 2° 58'. 2,600—0 m. 



Fig. 6, Pl. II represents a nearly related form from the same gathering. 



L. lineata (Ehb.). Pl. II, hg. 7. 



Deep-sea hauls: 



Date. 



Lat. N. 



Long. 



Depth. 



Fq. 



Pl. 



29—30 VII 



78' 13' 



2° 58' W. 



2,600—0 m. 



)• 



CS 



27 vni 



79° 58' 



9°35'E. 



400-0 > 



»• 



cs 



5 IX 



71=50' 



19° 2'E. 



230-0 » 



)■ 



s 



Habitat: Mediterranean, Atlantic, Indian and Pacific Oceans (Hkl.). 



