REPORT ON THE RADIOLARIA. 1207 



11. Lithomelissa haeckelii, Biitschli. 



LHhomelissa haeckelii, Butschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 517, Taf. xxxiii. 

 fig. 23, a, b. 



Shell rough, with sharp collar stricture. Eelative length of the two joints = 6:5, breaclth = 6:7. 

 Cephalis subspherical, large, with two divergent horns, a very large, obUque pyramidal occipital horn 

 on the summit, and a very small frontal horn on the middle of the forehead. Thorax campanulate, 

 little larger than the cephalis, with regular circular pores of twice the breadth. From the upper 

 part of the thorax, below the collar stricture, there arise three stout, divergent, angular, semi-lunar 

 feet, about as long as the shell. Mouth wide open, not constricted. 



Dimensions. — Cephalis O'OG long, 0'06 broad ; thorax 0'05 long, 0-07 broad. 



Ealitat. — Tropical Atlantic, Station 347, depth 2250 fathoms; fossil in Barbados. 



12. Lithomelissa hiltschlii, n. sp. (PI. 56, fig. 1). 



Shell smooth, with slight collar stricture. Eelative length of the two joints = 5:6, breadth = 4:5. 

 Cephalis ovate, large, with two small conical horns, which are opposed nearly horizontally, in the 

 upper part of the cephalis ; an anterior frontal and a posterior occipital horn. Thorax ovate, 

 truncate, little larger. Pores of l)oth joints irregular, roundish, of very different sizes. From the 

 middle part of the thorax there arise three short conical divergent feet. (In the figured specimen 

 there were some accessory thorns ; in another specimen, found afterwards, the surface was quite 

 smooth, but the two horns and the three feet much larger, half as long as the cephalis.) 



Dimensions. — Cephalis 0-05 long, 0-04 broad; 006 long, 0'05 broad. 



Habitat. — Central Pacific, Stations 266 to 274, depth 2350 to 2925 fathoms. 



Subgenus 3. Sethomelissa, Haeckel, 1881, Prodromus, p. 431. 



Definition. — Cephalis with three, four, or more horns, a primary occipital, a secondary 

 frontal, and one or more accessory parietal horns. 



13. Lithomelissa corythium, Ehrenberg. 



Lithomelissa corythium, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. iii. 

 fig. 12. 



Shell smooth, with slight collar stricture. Eelative length of the two joints = 4:3, breadth = 4:5. 

 Cephalis campanulate, with three short conical horns on the summit. Thorax flat and wide. Prom 

 its upper part below the collar stricture, there arise three divergent, pyramidal feet, fenestrated 

 at the base, about as long as the shell. Mouth wide open. (The specimen figured by Ehrenberg 

 was an incomplete one.) 



DiTnensions. — Cephalis 0'04 in diameter, thorax O^OS long, O'Oo broad. 



Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; fossil in Barbados. 



