248 THE VOYAGE OF H.M.S. CHALLENGEE. 



Eadial spines very strong, with dentated edges and with three rows of lateral branches (six dentated 

 curved branches on each edge). 



Dimensions. — Diameter of the outer shell 0-4, inner 0'13. 



Habitat. — Xortli Atlantic, Azores, surface. 



7. Diplosphwra reticulata, n. sp. 



Inner shell with regular, hexagonal meshes, five times as broad as the liars, which are 

 densely covered with very numerous, simple bristle-shaped by-spines ; outer shell four times as 

 broad, with very numerous small irregular polygonal meshes, forming a very delicate network, and 

 filling out the large triangular main meshes. Eadial spines with three serrated edges and three 

 rows of short curved branches (four to five branches on each edge). 



Dimensions. — Diameter of the outer shell 0'6, inner Olo. 



Habitat. — North Atlantic, Gulf Stream, Fseroe Channel, surface, John ilurray. 



8. Diplosphcera triglochin, n. sp. 



Inner shell with irregular, polygonal meshes and very thin thread-like bars ; outer shell three 

 times as broad, with similar irregular polygonal meshes, filling out the large triangular main meshes. 

 Eadial spines with three serrated edges, each of which bears one single large lateral liranch, 

 concavely curved towards the distal end. By-spines of the inner shell very numerous. 



Dimensions. — Diameter of the outer shell O'o, inner 01 7. 



Habitat. — Central Pacific, Station 264, surface. 



Genus 99. Drymosph(je}xi,^ Haeckel, 1881, Prodromus, p. 452. 



Definition. — A s t r o s p h se r i d a with two extracapsular cortical shells, connected 

 hy long prismatic, radial s^Diues ; outer shell with thin radial hy-spines. 



The genus DrymosplicBra differs from its ancestral form Leptosphcera in the 

 development of radial by-spines on the surface of the outer shell, the inner shell being 

 smooth. 



Subgenus 1. DrymosphcBrella, Haeckel. 

 Definitiori.—?\,&Aia\. by-spines simple, not branched (main spines simple). 



1.' Drymospliara hexagonalis, n. sp. 



Inner shell with regular, hexagonal meshes and very thin thread-like bars ; outer shell twice 

 as broad, with simple triangular meshes and thin thread-like bars, which bear very numerous, 



^ Vrymosph(tra = WooAy sphere ; i^vf^o;,' aipctl(;ci. 



