124 OPHIUROIDEA. 
Ophiopholis goodsiri, 7d. zed. 
Amphiura ballii, Sars, Nyt Mag. x. (1859) p. 42; td. Norg. Ech. 
(1861) p. 17, pl. 2. figs. 1-6; Norman, Ann. § Mag. xv. (1865) 
109 
Gaieiends ballii, Lyman, Cat. Mus. C. Z. i. (1865) p. 12. 
Ophiactis ballii, Lyman, Chall. Rep. (1882) p. 121; Hoyle, Proc. 
Roy. Soc, Ed, xii. (1884) p. 718; td. Proc. R. Phys. Soc. Ed. viii. 
(1885) p. 143. 
A small species, with fairly stout, moderately long arms. Disk- 
scales subequal, regularly imbricating, sometimes spiny. Radial 
shields small, wider without than within ; the inner apices widely 
separated from one another. A single mouth-papilla. Four or five 
arm-spines, two of which may be a little longer than the length of 
the side-plate ; the side-plates nearly meet in the middle line above, 
and the upper arm-plates are therefore very much wider along their 
distal than their proximal edge; lower arm-plates cordiform, with 
a rounded proximal edge. 
Colour, in spirit, white. ‘“ Disk yellowish or red, often mottled 
with these two colours; arms banded with red” (Norman). 
R=20 (about) ; r=3. 
Distribution. North Atlantic. 
a. East of Shetland Is., 203 fms. ‘Porcupine ’ Exp. (St. 74). 
b,c. Dalkey Sound. Belfast Nat. Hist. Society. 
d. Giants’ Causeway (adherent to Pinna). Belfast Nat. Hist. Society. 
Dr. Norman states that “it lives on hard ground, in deep water, 
and has a peculiar habit, delighting to nestle in hollows and crevices 
of stones, squeezing its disk and twisting its arms so as to conform 
to all the irregularities of the surface to which it attaches itself.” 
To 203 fms. 
5. OPHIOPUS. 
Ophiopus, Ljungman, Gifv. Vet.-Akad. Forh. 1866 (1867), p. 309; Ly- 
man, Chall. Rep, Oph, (1882) p. 156. 
Ophiaregma, Sars, Forh. Vid. Selsk. Christ. 1872 (1878), p. 112. 
Very near Ophiactis, but distinguished by the absence of bursal 
clefts. 
1. Ophiopus arcticus. 
Ophiopus arcticus, Ljungman, Gif. Vet.-Akad. Férh. 1866 (1867), 
p- 809; Lyman, Chall. Rep. Oph. (1882) p. 156; Hoyle, Proc. 
ftoy. Soe, Ed. xii. (1884) p. 720. 
Ophiaregma abyssorum, Sars, Forh. Vid. Selsk. Christ. 1872 (1873), 
p. 12: 
Disk pentagonal, with large central and five primary plates well 
marked ; radial shields very obscure. Arms delicate, about seven 
times the radius of the disk; three or four short arm-spines, the 
