136 OPHIUROIDEA. 
a. North-west of Shetland, 345 fms. ‘Porcupine’ Exp. (St. 63). 
b. Off S.W. coast of Ireland, 315 fms. ‘Flying Fox’ Exp. 
ec, Off S.W. coast of Ireland, 400 fms. G. C. Bourne, Esq. 
Distribution. These are the only known habitats. 
3. OPHIOMYXA. 
Ophiomyxa, M. Tr. Syst. Ast. (1842) p. 108; Lyman, Chall. Rep. Oph. 
(1882) p. 244. 
Disk and arms covered by a thick skin. Mouth-papille and teeth 
flattened lobes, with serrate edges. No tentacle-scales. Arm- 
spines jagged at tip. 
1. Ophiomyxa serpentaria. 
Ophiomyxa serpentaria, Lyman, Bull. M.C. Z. x. (1888) p. 274; Hoyle, 
Proc. Roy. Soc, Ed, xii. (1884) p. 710. 
A single specimen, reported by Lyman from 363 fms. in Faeroe 
Channel, and distinguished by the absence of upper arm-plates, 
three short arm-spines, and three small mouth-papille; radial 
shields small *. 
CLADOPHIURE (see p. 26). 
ASTRON YCIN A (see p. 27). 
ASTRONYX. 
Asteronyx, M. Tr, Syst. Ast. (1842) p. 119; Norman, Ann. § Mag. 
xv. (1865) p. 105. 
Astronyx, Lyman, Chall. Rep. Oph. (1882) p. 285. 
Disk pentagonal, arched, sharply separated from the narrow 
arms ; radial shields in the form of elongated rods, but broken into 
several pieces. Papille on the angles of the mouth large ; mouth- 
shields hidden and small, as is the madreporite. Basal clefts set in 
a depression, very short, and in the interbrachial angle only. Some 
of the arm-spines hooked. 
1. Astronyx loveni. 
Asteronyx loveni, IZ. Tr. Syst. Ast. (1842) p. 119; Sars, Norg. Ech: 
(1861) p. 5, pl. i. figs. 1-56; Stewart, P. Z. 8. 1861, p. 96 (fig.) 5 
Norm. Ann. § Mag. xv. (1865) p. 106; Jarzynsky, Trans. Petersb- 
Soc. Nat. i. (1870) p. 318; Lyman, Chall. Rep. Oph. (1882) 
p. 187; Stim, Zoologist, xl, (1882) p. 24; Hoyle, Proc. R. Phys. 
Soc. Ed. viii. (1884) p. 187; id. Proc. Roy. Soc, Ed. xii. (1884) 
p. 713. 
Arms very long, slender, convex above, flattened below, very fine 
* No specimen is in the British Museum. 
