REPORT ON THE RADIOLARIA. 87 



The genus Styptosphcera presents a spherical shell with smooth or rough 

 surface (without radial spines), the whole mass of which is composed of looser or 

 denser spongy wicker-work. 



1. Styptosphcera spumacea, n. sp. 



Spongy framework of the solid sphere loose, with large polygonal meshes of slightly different 

 size, ten to twenty times as broad as the bars. Structure of the whole spongy sphere the same. 

 Central capsule filled with crystals. Surface smooth. 



Dimensions. Diameter of the sphere 0'32, of the central capsule 0'26, meshes O'Ol to 0'02, 

 bars O'OOl. 



Habitat. North Pacific, Station 236, surface. 



2. Styptosphcera spongiacea, n. sp. 



Spongy framework in the central part of the solid sphere much more compact than in the 

 peripheral part, becoming gradually looser towards the rough surface. Meshes in the centre 

 three to five times, in the periphery fifteen to twenty times as broad as the bent bars. 



Dimensions. Diameter of the sphere 0'45, inner meshes O'OOG to O'Ol, outer meshes 0'03 to 

 0-04, bars 0'002. 



Habitat. Central Pacific, Station 271, surface. 



3. Styptosphcera stupacea, n. sp. 



Spongy framework of the solid sphere rather compact, everywhere of the same structure, with 

 roundish, nearly equal meshes, six to eight times as broad as the bars. Surface rough with 

 prominent thorns. 



Dimensions. Diameter of the sphere 0'22, meshes O'Ol to 0'012, bars 0'0015. 



Habitat. South Pacific, Station 291, surface. 



Genus 26. Plegmosphcera, Haeckel, 1 1881, Prodromus, p. 455. 



Definition. L iospserida forming a hollow sphere of spongy framework, without 

 a medullary shell in the central cavity. 



The genus Plegmosphcera develops a large hollow sphere, the wall of which is 

 composed of looser or denser spongy wicker-work. On the inner as well as on the 

 outer face of the spongy shell-wall may be present a simple lattice-sphere from which 

 the threads of the framework arise ; but in some species these lattice-plates are quite 

 absent. 



1 Plegmosphcera = Sphere of wicker-work ; xhtypa, alfa^ec. 



