1302 THE VOYAGE OF H.M.S. CHALLENGER. 



3. Sethocorys armadillo, Haeckel. 



Eucyrtidium armadillo, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, 



Taf. ix. fig. 10. 



Shell slenderly ovate, smooth, with deep collar stricture. Length of the two joints = 3 : 10, 

 breadth = 4:6. Cephalis ovate, at the apex thorny, with a conical horn of the same length. 

 Thorax smooth, ovate, truncate, with small, regular, circular pores, disposed in from twelve to fifteen 

 transverse rows of the same breadth as the cephalic pores. Mouth constricted, half as broad as 

 the thorax, with a broad, hyaline, prominent peristome. 



Dimensions. — ^Cephalis 0'03 long, 0-04 broad ; thorax 01 long, 0'06 broad. 



Habitat. — Fossil in Barbados. 



4. Sethocorys odysseus, n. sp. (PL 62, fig. 10). 



Shell ovate, smooth, with obliterated collar stricture. Length of the two joints = 2:9, 

 breadth = 4:8. Cephalis hemispherical, with a slender, conical horn of the same length. Thorax 

 nearly spherical, with regular, circular pores, of the same breadth as the cephalic pores, quincun- 

 cially disposed. Mouth constricted, only one-third as broad as the thorax, with a broad, hyaline, 

 prominent peristome. 



Dimensions. — Cephalis 0-02 long, 0"04 broad ; thorax 0-09 long, 0'08 broad. 



Hahitat. — Central Pacific, Station 272, depth 2600 fathoms. 



5. Sethocorys ami^hora, Haeckel. 



Lophophcena ainpliora, Stbhr, 1880, Palseontogr., vol. xxvi. p. 99, Taf. iii. fig. 11. 



Shell ovate, mouth with distinct collar stricture. Length of the two joints=l:5, 

 breadth = 2:4. Cephalis hemispherical, with a short conical horn of half the length. Thorax 

 ovate, truncate, with small, regulai-, circular, quincuncial pores. Mouth constricted, half as broad 

 as the thorax, with a narrow, prominent, hyaline peristome. 



Dimensions. — Cephalis O^OIS long, O'OS broad ; thorax 0'07 long, 0'06 broad. 



Habitat. — Fossil in Tertiary rocks of Sicily ; Grotte (Stohr). 



6. Sethocorys ajacis, n. sp. 



Shell slenderly ovate, smooth, without external collar stricture, but with an internal septum. 

 Length of the two joints = 1:3, breadth = 1:2. Cephalis conical, with a large pyramidal horn of 

 twice the length, and sometimes with a smaller accessory horn at its base ; its pores scarce, 

 irregular. Thorax ovate, truncate, hyaline, in the greater part without pores, in the smaller part 



