REPORT ON THE RADIOLARIA. 1403 



inflated, nearly spherical, truncate at both poles, separated by a deep stricture from the ceplialis, as 

 well as from the conical abdomen, which is dilated gradually towards the wide mouth. Pores in 

 the thorax subregular, circular, in the abdomen twice to four times larger, and irregular. 



Dimensions. — Length of the three joints, a 0'02,, 6 0'06, c O'l ; breadth, a 0'02, h 0'08, c 01. 



Habitat. — Fossil in Barbados. 



13. Tlieoconus laterna, u. sp. 



Shell conical, smooth. Length of the three joints = 1:2:4, breadth = 1:2:4. Cephalis 

 small, ovate, with a strong, pyramidal, vertical horn three times the length. Thorax hemispherical, 

 with subregular, circular, hexagonally-framed pores. Abdomen truncate, conical, with only fifteen 

 to twenty very large, irregular, polygonal pores, which are separated by very thick bars of the same 

 breadth as the horn. 



Dimensions. — Length of the three joints, a 0"03, b O'OG, c 012 ; breadth, a 0'03, b 0'07, c 012. 



Habitat. — Central Pacific, Station 266, depth 2750 fathoms. 



14. Theoconus Jicus, Haeckel. 



Eucyrtidinm ficiis, Ehrenberg, 1875, Abhandl. d. k, Akad. d. Wiss. Berlin, p. 70, Taf. xi. 



fig. 19. ■ 

 Theocorys fictis, Haeckel, 1881, Prodromus, p. 434. 



Shell conical, pear-shaped, smooth. Length of the three joints = 1 : 5 : 20, breadth = 2 : 10:25. 

 Cephalis very small, ovate, with a conical, straight horn three times the length. Thorax quite 

 conical, with solid wall, without pores. Abdomen very large, nearly spherical, truncate at both 

 poles, little constricted at the very wide mouth ; its pores subregular, circular, about three times as 

 broad as the bars. (This species is intermediate between the genera Theoconus and Theocorys.) 



Dimensiom. — Length of the three joints, a O'Ol, b 0-05, c 0'2 ; breadth, a 0'02, b 01, c 0'25. 



Habitai. — Fossil in Barbados. 



Genus 614. Lophoeonus} n. gen. 



Definition. — T heocorida (vel Tricyrtida eradiata aperta) with conical abdomen 

 oradually dUated towards the wide open mouth. Cephalis with two or more horns or 

 a corona of horns. 



The genus Lophoconus has the same conical shell with truncate mouth as Theoconvs, 

 and differs from it only in the armature of the cephalis, bearing either two large diver- 

 gent horns (usually a larger occipital and a smaller frontal horn), or a bunch or 

 corona of numerous divergent horns. 



1 iop/iocowMs = Cone with a crest ; Xo'^oj, xuvo;. 



