80 _ THE VOYAGE OF H.M.S. CHALLENGER. 
abraded (?). On some of the plates on the inner part of the ray there is a small rudi- 
mentary lateral spinelet, which, although much larger than the other spinelets on the plates, 
is scarcely discernible without a magnifying glass. This does not appear to be present on 
all the plates, and I find no trace of its existence on the outer part of the ray. In the 
interbrachial arcs two or three plates bear very large pedicellarian apparatus formed of 
three or four comparatively long and robust spines. This is usually placed near the 
junction of the infero-marginal with the supero-marginal plates; and there may occa- 
sionally be one similarly placed further out on the ray. 
The adambulacral plates are long and very narrow, with the furrow margin very faintly 
convex. Their armature consists of :—(1.) A furrow series of five or six short, cylindrical, 
obtusely tipped spinelets, subequal in size, except the outer one of the series, which is 
sometimes smaller. ‘They appear to stand parallel to one another, forming a compact 
series, and the successive series are widely spaced apart. (2.) Immediately behind the 
furrow series, on the actinal surface of the plate, is a lineal series of three or four spinelets 
precisely similar in size and form, closely appressed to the furrow series ; and there are no 
other spinelets or granules on the adambulacral plates. 
The mouth-plates are large and elongate. The pair together are slightly convex 
actinally, and the median suture is widely open. The armature consists of a marginal 
series of nine or ten small, short, obtuse, papilliform spinelets on each plate, the innermost 
one of which is rather larger and more robust than the others. On the actinal surface of 
the plates are a few irregularly placed papilliform granules, showing to a certain extent a 
tendency in places to form a second series behind the marginal series; one or two of the 
papilla at the anterior end of the plate are larger than the others. 
The actinal interradial areas are remarkably small and limited ; and there are not more 
than from four to six very small intermediate plates in each. These plates bear small, 
isolated, papilliform granules, and there may be two or more pedicellarian apparatus, 
similar to those described in the interbrachial arcs, in each area. 
The tube-feet have a terminal knob, which is large when compared with the small size 
of the Asterid. 
The anal aperture is slightly excentrie and difficult to distinguish. 
The madreporiform body is rather large; and with very coarse striations, and is situated 
close to the marginal plates. It is more or less concealed by paxille. 
Colour in alcohol, clear white. 
Locality.—Station 198. In the Celebes Sea, between Celebes and Mindanao. October 
20, 1874. Lat. 2° 55’ 0” N., long. 124° 53’ 0” E. Depth 2150 fathoms. Blue mud. 
Bottom temperature 38°°9 Fahr. ; surface temperature 85°'0 Fahy. 
ftemarks.—There seems to me little doubt that this is an immature specimen. Still it 
is very distinct from any species hitherto known, and its characters have appeared to me 
sufficiently well-marked to justify its recognition by name. At first sight the marginal 
