KONGL. SV. VET. AKADEMIENS HANDLINGAR. HAND 34. \:o I. 



Hexacontinm armatnm. N. Sp. 



Plate VI. Fig. 5. 



Cortical shell thick-walled, with regular, honeycomb-Kke network. Meshes funnel- 

 shaped, with circular inner and hexagona] outer aperture, as broad as the bars, aboul 7 

 on the radius. Main spines strong, three-sided prisrnatic, as long as the radius of fche 

 outer shell. By-spines at every nodal point, short, bristle-like. Radia] proportion of the 

 three shells 1:3: 8. 



Diameter 0,n; length of the raain spines 0,06; basal breadth of the main spines 0,02; 

 diameter of the meshes 0,oi millim. 



Rare at 56° N. 17°. W. (November 1898). Tentperature 11,6. Salinity 35,27. Styli- 

 plankton. 



Nearest akin to H. favosum, from which it differs by the smaller meshes and 

 the stronger main spines. 



Hexacontiuni hostile. N. Sp. 



Plate VI. Fig. 4. 



Radial proportion of the three shells 1:3:9. Outer shell thick-walled, with ir- 

 regular, rounded pores, 1 to 5 times as broad as the bars. Main spines strong, three- 

 sided prisrnatic, slightly spirally twisted, twice as long as the radius. By-spines bristle- 

 like as long as the diameter of the pores. 



Diameter of the outer shell 0,09, of the middle 0,03, of the inner 0,009; diameter 

 of the pores 0,006 to 0,oi6; length of the main spines 0,08, their basal breadth 0,024 millim. 



Rare at 56° N. 23° W. (November 1898). Temperaturs 10,8. Salinity 3ö,32. 



Hexacontiuni setosum Hkl.? 



Plate V. Fig. 6. 



This species (Chall. Rep. Radiol. pag. 198) has not been figured, of which reason 

 the identification is doubtful. The radial proportion of the three shells 1:4:7. Diameter 

 of the outer shell 0,u, of the middle 0,04, of the inner 0,02; diameter of the cortical pores 

 0,oi to 0,03; breadth of the bars 0,004; length of the main spines 0,oe millim. 



Rare at 45° N. 49° W. (January 1899). Temperature 12. Salinity 35,54. 



My specimen occurred in styli- and trichoplankton intermingled. 



Hexastylus nobilis. N. Sp. 



Plate VI. Fig 1. 



Shell thick-walled. Pores regular circular, hexagonally framed, 10 on the radius. 

 Six main spines triangulär pyramidal, with straight edges, as long as the radius; their 



K. Sv. Vet. Akad. Handl. Baud 34. N:r 1. 2 



