1292 THE VOYAGE OF H.M.S. CHALLENGER. 



concave outlines, and subregular, hexagonal pores, gradually increasing towards the mouth, the 

 largest half as broad as the cephalis. This elegant species is dedicated to Dr. Eay, the discoverer 

 of many rare Eadiolarians in the Challenger collection. 



Dimensions. — Cephalis 0'03 long, 0'02 broad ; thorax 0'08 long, 012 broad. 



Habitat. — Central Pacific, Stations 26G to 272, surface. 



7. Sethoconus cervus, Haeckel. 



1 Eucyrtidium cervus, Ehrenberg, 1872, Abhandl. d. k. Akad. d. "Wiss. Berlin, p. 291, Taf. ix. 

 fig. 21. 

 Cunaracliniimi cervus, Haeckel, 1881, Prodromus, p. 430. 



Cephalis subspherical, with slight collar stricture, small circular pores, and two to four di\-ergent 

 horns, one or two of which are forked. Thorax wide, conical, about as long as broad, with straight 

 outlines and irregular, polygonal pores, gradually increasing towards the mouth ; the largest as 

 broad as the cephalis. 



Dimensions. — Cephalis O'Olo long, 0'02 broad ; thorax 0'08 long, O'OS broad. 



Habitat. — Indian Ocean ; Maldive Islands, surface (Haeckel) ; Zanzibar, depth 2200 fathoms 

 (Pullen). 



8. Sethoconus loj^hoj^hcena, u. sp. 



Conarachnium loplioplicvna, Haeckel, 1881, Prodromus, p. 430. 



Cephalis subspherical, with distinct collar stricture, small circular pores, and numerous (twelve 

 to sixteen) radial, bristle-shaped horns of diflerent lengths. Thorax wide, conical, somewhat longer 

 than broad, with slightly convex outlines, and subregular, hexagonal pores, increasing gradually in 

 size towards the mouth ; the largest twice as broad as the cephalis. 



Dimensions. — Cephalis 0'03 long, 0-04 broad ; thorax 0'2 long, 0-16 broad. 



Habitat. — South Pacific, Station 300, depth 1375 fathoms. 



9. Sethoconus larvatus, Haeckel. 



Loplwphana larvata, Ehrenberg, 1875, Abliandl. d. k. Akad. d. "Wiss. Berlin, p. 78, Taf. viii. 



fig. 10. 

 Didyocsphalus larvatus, BUtschli, 1882, Zeitsclir. f. wiss. Zool., Bd. xxxvi. p. 535. 



Cephalis subspherical, large, with sliarp collar stricture, and numerous (five to ten or more) 

 radial, conical (partly forked) horns of different lengths. Thorax wide, conical, somewhat broader 

 than long, with straight outlines. Pores of both joints very irregular, roundish, of very different 

 sizes and form. 



Dimensions. — Cephalis 0-04 long, O'Oo broad ; thorax O'i long, 012 broad. 



Habitat. — Fossil in Barbados. 



