ANNOTATED LIST. 105 
A few species, however, as Ophiocoma pica and Ophiomastix asperula, seem to be 
really rare, for in spite of their conspicuous character and of special effort being 
made to find them, very few individuals were found. Brittle-stars are much more 
active than sea-stars and are much more disposed to avoid bright light. Overturn- 
ing of their shelter, or breaking up of a coral cluster, leads at once to active flight 
in the effort to reach another shelter. In activity of movement and ability to escape, 
the magnificent Ophiomastix janualis is facile princeps, and the capture of an 
uninjured specimen requires quickness and skill, much helped by experience. 
TRICHASTERID/E. 
Euryale aspera. 
Lamarck. 1816. Anim. s. Vert., 2, p. 538.—Ddéderlein. 1911. Japan. Euryal, p. 65, pl. 5, figs. 7, 7a. 
This characteristic East Indian basket-fish ranges from Okinawa, in the Riu Kiu 
Islands (lat. 26° N.) to Double Island Point, Queensland (lat. 26° S.). The Challenger 
found it near Wednesday Island, in 8 fathoms, but we did not find it near Mer. As it is 
known from the Aru Islands and is not known from any point on the north coast of New 
Guinea or east of that island, it would seem to be one of those species which has passed 
through Torres Strait in the southward extension of its range. Déderlein (1911) lists it 
from West Australia, no doubt on the strength of Studer’s (1884) record of two young 
specimens taken by the Gazelle in 50 fathoms off Dampier’s Archipelago. But it must be 
remembered that these specimens were very young (disks, 5 to 8 mm. across) and neither 
specific nor generic characters are clearly indicated at such an age. 
OPHIACANTHID£E. 
Ophiacantha confusa. 
Koehler. 1905. Siboga Oph. litt., p. 59, pl. vii, figs. 9-11. 
This species was described originally from a single specimen taken in 20 fathoms at 
the island of Salibabu, Dutch East Indies, and I refer to it two small ophiacanthas taken 
from a piece of dead coral far out on the southwestern reef at Mer, October 27, 1913. 
Koehler’s specimen had the disk, somewhat damaged, 3 mm. across and the arms 18 mm. 
long; the individuals from Mer are of the same size. The spinules of the disk terminate in 
much longer teeth in the Murray Island specimens than those shown in Koehler’s figure, 
and the ends of the radial shields are not completely concealed. ‘The chief difference, 
however, is in the basal under arm-plates which are diamond-shaped and not at all oblong, 
as shown in the published figure. These differences seem to me too trivial to be considered 
as due to anything more than “‘individual diversity”’ in the brittle-stars and the ‘‘personal 
equation” in the observers. In life, the specimens from Mer had the disk pale greenish 
and the arms banded with lighter and darker brown; the dry specimens are pale brown and 
whitish, with the banding of the arms barely indicated. 
Ophiacantha discoidea. 
Lyman. 1879. Bull. M. C. Z., 6, p. 57, pl. xv, figs. 405-407. 
(Plate 12, Figure 4.) 
This is another little-known species taken by the Challenger in the Arafura Sea, at a 
depth of 49 fathoms. It was not taken by the Siboga and so far as I can discover has not 
been met with since the Challenger found it. We took 4 specimens with a tangle off the 
west reef at Mer, in 4 to 5 fathoms of water, October 7, 1913. The smallest specimen has 
the disk less than 2 mm. across and, of course, is not certainly identifiable. The largest 
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