REPORT ON THE RADIOLARIA. 141 



Dimensions. Diameter of the outer sphere O'll, pores O'Ol to O'OlV, bars 0'003 to 0'007; 

 diameter of the inner sphere 0'06, pores 0'05 to O'OOS, bars 0'002 to 0'004; length of the major 

 polar spine 0'25, of the minor 01, basal breadth 0'03. 



Habitat. Indian Ocean, Madagascar, Eabbe, surface. 



Genus 50. Saturnulus, 1 Haeckel, 1881, Prodromus, p. 451. 



Definition. Sty losphserida with two concentric lattice-spheres and two equal 

 opposite spines, the distal ends of which are connected by a circular or elliptical ring. 



The genus Saturnulus differs from the similar Saturnalis by the duplication of the 

 spherical lattice-shell ; the inner lies within, the outer without the central capsule. 



1. Saturnulus circulus, n. sp. 



Cortical shell smooth, twice as broad as the medullary shell, with regular, circular, hexagonally 

 framed pores, of the same breadth as the bars ; fourteen to sixteen on the half equator. King 

 circular, smooth, without edges, its diameter three times as great as that of 'the sphere. 



Dimensions. Diameter of the outer sphere O'OS, pores and bars 0'004 ; of the inner sphere 0'04, 

 of the ring 0'24. 



Habitat. Central Pacific, Station 272, surface. 



2. Saturnulus annulus, n. sp. 



Cortical shell smooth, three^ times as broad as the medullary shell, with regular, circular, 

 hexagonally framed pores, of the same breadth as the bars ; eighteen to twenty on the half equator. 

 King elliptical, smooth, without edges, somewhat constricted at the poles of the minor axis, its 

 major diameter four times as great as that of the sphere. Differs from Saturnalis annularis, PI. 13, 

 fig. 16, mainly in the possession of a medullary shell. 



Dimensions. Diameter of the outer sphere O'l, pores and bars 0'005 ; inner sphere 0'033 ; 

 major axis of the ring 0'4, minor 0'3. 



Habitat. North Pacific, Station 244, surface. 



3. Saturnulus ellipticus, n. sp. (PI. 16, fig. 16). 



Cortical shell smooth, three times as broad as the medullary shell, with regular, circular pores, 

 three times as broad as the bars ; sixteen to eighteen on the half equator. King elliptical, smooth, 

 ^without edges, its major diameter three times as great as that of the sphere. 



Dimensions. Diameter of the outer sphere 0'09, pores O'OOG, bars 0'002 ; inner sphere 0'03 ; 

 major axis of the elliptical ring 0'28, minor 0'24 ; thickness of the ring and the axial beams O'OOS. 



Habitat. South Pacific, Station 300, surface. 



1 Saturnulus Small Saturnus, with a ring. 



