REPORT ON THE RADIOLARIA. 269 



3. Arachnosphcera dolichacantha, n. sp. 



Innermost shell with regular, hexagonal meshes, very small ; its diameter only as long as the 

 equal distances between every two concentric shells. At each nodal-point occurs one radial spine 

 with twelve to sixteen verticils (altogether thirty to forty spines). 



Dimensions. Diameter of the innermost shell 0'05 ; distance between the concentric shells 0'04 

 to 0-05. 



Habitat. Central Pacific, Station 265 to 274, surface. 



4. Arachnosphcera increscens, n. sp. 



Innermost shell with regular, hexagonal meshes ; its diameter three times as long as the 

 distance between it and the second shell, quite as long as the distance between the fifth and sixth 

 shells ; the distances between the concentric shells gradually increasing from the centre. Eadial 

 spines about fifty to sixty, each with six to eight verticils. 



Dimensions. Diameter of the innermost shell (A) 075 ; distances between the following shells 

 A, B = 0-025, B, = 0-037, C, D = 0'05, D, E = 0'062, E, F = 0-075, &c. 



Habitat. Central Pacific, Station 271, surface. 



Subgenus 2. Arachnosphceromma, Haeckel. 

 Definition. Pores of the innermost shell irregular, polygonal. 



5. Arachnosphcera tenuissima, n. sp. 



Innermost shell with irregular, polygonal meshes ; its diameter twice as long as the equal dis- 

 tance between every two concentric shells. Forty to fifty radial spines, each with twelve to sixteen 

 verticils. 



Dimensions. Diameter of the innermost shell 01, distance between the concentric shells 0'04 

 to 0-05. 



Habitat. South Atlantic, Station 332, surface 



6. Arachnosphcera velaris, n. sp. 



Innermost shell with irregular, polygonal meshes ; its diameter twice as long as the distance 

 between it and the second shell, quite as king as the distance between the third and fourth shells ; 

 the distance between the concentric shells gradually increasing from the centre. Radial spines twenty 

 to thirty, each with ten to twelve verticils. 



Dimensions. Diameter of the innermost shell (A) 0'5 ; distances of the following shells A, B 

 = 0-025, B, C = 0-037, C, D = 0'05, D, E = 0'062, E, F = 0-075. 



Habitat. Tropical Atlantic, Station 347, surface. 



