REPORT ON THE RADIOLARIA. 89 



5. FlegmospJupra leptodictijon, n. sp. 



Radius of the spongy shell-cavity six times as great as the tliickiiess of tlie spongy wall. 

 Inside of the wall closed by a smooth lattice-plate, outside rough spongy. 

 Dimensions. — Diameter of the shell 0'44, of its cavity 0'36. 

 Habitat. — Central Pacific, Station 266, surface. 



Subgenus 3. PIcgmos2)hcBromma, Haeckel. 



Definition. — Inside of the spongy shell-wall rough spongy, without lattice-plate, 

 outside closed by a smooth lattice-plate. 



6. Plegmosphcera exodictyon, n. sp. (PI. 18, fig. 8). 



Radius of the spongy shell-cavity only one-fourth as great as the thickness of the spongy shell- 

 wall. Outside of the wall closed by a smooth lattice-plate, inside rough, spongy. 

 Dimensions. — Diameter of the shell 0'4, of its cavity 0'08. 

 Habitat. — South Atlantic, Station 325, surface. 



Subgenus 4. Plegmosphmrusa, Haeckel. 



Definition. — Inside and outside of the spongy shell-wall rough, with spongy or 

 spiny surface, without lattice-plate. 



7. Plegmosphcera leptoplegma, n. s]). 



Radius of the spherical shell-cavity half as great as the thickness of the loose spongy .shell-wall. 

 Inside and outside of the wall rough spongy, not closed by a lattice-plate. Jleshes ten to twenty 

 times as broad as the bars. 



Dimensions. — Diameter of the shell 0"3, of its cavity 0'088. 



Habitat. — North Atlantic, Station 253, surface. 



8. Plegmosphcera pachyplegma, n. sp. 



Radius of the spherical shell-cavity about equal to the thickness of the dark and dense 

 spongy shell-wall. Inside and outside of the wall rough spongy, not closed by a lattice-plate. 

 Meshes three to five times as broad as the bars. 



Dimc7isions. — Diameter of the .shell 0'2, of its cavity O'l. 



Habitat. — Central Pacific, Station 270, surface. 



Genus 27. Spongoplegma} Haeckel, 1881, Prodi'omus, p. 455. 



Definition. — L i o s p h te r i d a forming a sphere of sjjougy framework, which encloses 

 in the centre one single latticed medullary shell. 



' ySponjropfef/'ma = Spongy wickerwork ; ar.iy/o;, vhty/ict. 



(ZOOL. CHALL. EXP. PART XL. — 188.5.) Rr 1 2 



