REPORT ON THE ASTEROIDEA. 613 
onthe ovarial region, of the narrowest and most attenuated description. It is further 
characterised by the absence of tegumentary prickles in the abactinal membrane, by the 
single small inner spinelet in the armature of the adambulacral plates, and by the com- 
paratively short lateral spines. 
7. Brisinga discincta, n. sp. (Pl. CX. figs. 4-7). 
Disk and number of rays unknown. R=180 mm. Breadth of.a ray at the base, 
4 mm. ; across the middle part of the ovarial region, 3°8 mm. (measured at 14 mm. from 
the base); and at 100 mm. from the base, 2°75 mm. 
Rays elongate and tapering throughout from the base, no special ovarial inflation 
perceptible ; subcylindrical and depressed at the base but still with a subtriangular 
tendency; at a short distance from the base the true subtriangular form is assumed, 
the vertical height in proportion to the breadth being somewhat greater than usual, with 
the converging slopes straighter and less incurved, and the median carination narrow 
but sharply truncate. 
Two ray fragments, which measure 114 and 66 mm. respectively, I believe from their 
width and general appearance to have both belonged to one ray; even in this case the 
terminal portion is still wanting to form an estimate of the full length. 
The abactinal surface of the ray is covered with an extremely thin and delicate mem- 
brane ; at the base of the ray there are two or three transverse annular bands, none really 
complete, of small narrow spicular plates, and rudiments of one or two still more incom- 
plete, consisting of only one or two small plates at the margin of the ray, These are 
the aborted representatives of the annular ridges in other forms, and no other spicules 
are present in the membrane beyond this point in the species under notice. Tolerably 
numerous small pedicellarie are present upon the membrane along the ray, and were 
probably disposed in transverse bands, this being distinctly the arrangement on the 
proximal part of the ray. 
The ambulacral furrow is wide and measures 1°25 mm. at a part where the ray is 
3 mm., about 40 to 50 mm. from the base. The adambulacral plates are fully twice as 
long as broad, measuring 2 mm. at about 50 mm, from the base. Both the furrow-margin 
and the outer margin are considerably incurved, and the ossicle is slightly flattened 
actinally and has somewhat of a twisted appearance when viewed from above; the adoral 
end is convex, the aboral concave, and the plates overlap considerably. The adambulacral 
armature consists of :—(1.) normally four small inner spinelets directed horizontally over 
the furrow, though sometimes only three are present; (2.) a small actinal spine standing 
perpendicularly on the actinal side of the plate; (3.) a long delicate lateral spine, articu- 
lated on a small rudimentary infero-marginal plate, corresponding to every third adambu- 
Jacral plate, 7.e. two unarmed adambulacral plates intervene between each successive lateral 
spine. Of the small inner spines, two, which stand close together and often one rather 
