EEPORT ON THE RADIOLARIA. 863 



Spines compressed, triangular, gradually tapering towards both ends ; outer half a little longer, and 

 much broader than the inner. 



Dimensions. Length of the shell 014, breadth 012 ; length of the spines 0'08, basal breadth 

 0-025. 



Habitat. Central Pacific, Station 274, surface. 



Genus 372. Belonaspis, 1 Haeckel, 1862, Prodromus, p. 468. 



Definition. B elonaspida with forty parmal pores (two on each plate), without 

 dimples and crests, but with numerous by-spines on the surface. 



The genus Belonaspis differs from its ancestral genus Thoracaspis only in the 

 possession of numerous superficial by-spines, and bears therefore to it the same relation 

 as Diporaspis does to Dorataspis. The two latter differ from the two former in 

 the spherical form of the central capsule and the enclosing shell, which here becomes 

 ellipsoidal. 



1. Belonaspis pandanus, n. sp. 



Parmal pores elliptical, three or four times as large as the circular sutural pores. Each plate 

 surrounded by five or six sutural pores (a single one on each side). Spines compressed, triangular ; 

 outer part half as long as the inner, and twice as long as the numerous, simple, bristle-shaped 

 by-spines. 



Dimensions. Length of the ellipsoidal shell (or major axis) 012, breadth (or minor axis) 01 ; 

 length of the spines 0'03, basal breadth 0'02. 



Habitat. South Pacific, Station 295, surface. 



2. Belonaspis furcata, n. sp. 



Parmal pores elliptical, twice as broad as the circular sutural pores. Each plate surrounded by 

 five or six sutural pores (a single one on each side). Spines compressed, linear, very thin ; outer part 

 longer than the inner. By-spines very numerous, half as long as the radius, furcate, with divergent 

 fork-branches. 



Dimensions. Length of the shell 01, breadth 0'08; length of the spines 012, breadth 0'003. 



Habitat. Indian Ocean (Cocos Islands), Eabbe, surface. 



3. Belonaspis datura, n. sp. (PI. 139, fig. 9). 



Parmal pores elliptical, three or four times as large as the circular sutural pores. Each plate 

 surrounded by ten or twelve sutural pores (two on each side). Spines triangular, two-edged, about 



1 Belonaspis Arrow-shield ; Athow, *o*!s- 



