KONGL. SV. VET. AKADEMIENS IIANDLINGAH. BAND 34. N:0 i. 



Hexacoutium nrmatnni. N. Sp. 

 Plate VI. Fig. 6. 



Cortical shell thick-walled, witli regular, honeycomb-like network. Meshes funnel- 

 shaped, with circular iiinci- ;ind hexagonal outer apei^ture, as l)road as the bars, about 7 

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

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

 three shells 1:3:8. 



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

 diameter of the meshes 0,oi millim. 



Rare at 56 N. 17. W. (November 1898). Tnuperature 11,6. Snlinity 35,27. Styli- 

 Ijlankton. 



Nearest akin to H. favosuin, from which it differs b)- tlie smaller meshes and 

 the stronger main spines. 



Hexacontium 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 prismatic, slightly spirally twisted, t^\ice 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,o3, of the inner 0,oo9; diameter 

 of the pores 0,oo6 to 0,oi6; length of the main spines 0,os, their basal bi-eadth 0,024 millim. 



Rare at 56 N. 23 W. (November 1898). Temperature 10,8. Salinity 35,32. 



Hexacontium setosuiu 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,i4, of the middle 0,04, of the inner 0,02; diameter of the cortical pores 

 0,01 to 0,03; breadth of the bars 0,oo4; length of the main spines 0,06 millim. 



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



My specimen occurred in styli- and trichoplankton intermingled. 



Hexastjius nobilis. N. Sp. 

 Plate VI. Fig 1. 



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

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



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



