REPORT ON THE ASTEROIDEA, 795 
5. Dytaster xquivocus, n. sp. (P]. XXXVI. figs. 5 and 6; Pl. XX XIX. figs. 10-12). 
Rays five. R=18mm.; r=475mm. R<47r. Breadth of a ray between the first 
and second supero-marginal plates, 4°25 mm. 
Rays moderately long and robust, tapering gradually from the extreme base to the 
extremity. Disk small. Interbrachial ares rather angularly rounded. Abactinal surface 
subplane, subject to slight inflation, with a central conical peak. Actinal surface plane. 
Lateral walls rather high, rounded towards the abactinal and actinal surfaces. 
The paxillz of the abactinal surface are small and well-spaced, borne on comparatively 
large basement plates, with a large, low, robust, tuberculose central eminence upon which 
the crown is attached. The crown is composed of five to eight short, equal, papilliform 
granules (occasionally with a tendency to the spiniform character), which are disposed in 
a compact group, or radiate only very slightly apart. At the sides, near the base of the 
ray, the paxillze show a tendency to be disposed in transverse series, more distinctly seen 
in some specimens than in others. The paxille are smaller on the flanks of the central 
cone and on the outer part of the rays. 
The supero-marginal plates, sixteen in number from the median interradial line to the 
extremity, are large, and form a well-defined border to the disk and rays, When viewed 
from above their breadth is slightly greater than their length—this being an apparent 
rather than a real dimension, caused by the arching or curvature of the plate toward the 
abactinal surface. The median region of the plates is slightly tumid, but there is no 
definite channel between adjoining plates as in Astropecten. The supero-marginal plates 
bear a small, low, robust, papilliform tubercle near the upper margin, the largest being in 
the median region of the ray. This tubercle is greatly aborted or absent altogether on 
the innermost plate on each side of the median interradial line, and perhaps also at the 
extremity of the ray. The surface of the plate is covered with small uniform papilliform 
granules, rather widely spaced, except at the vertical margins of the plates. 
The infero-marginal plates correspond exactly to the superior series, which are directly 
superposed, Their surface is covered with low papilliform granules, widely spaced on the 
median area on the actinal region of the plate. The plates bear on the rounded angle that 
unites the lateral and actinal areas of the test, or sometimes further upon the former, a 
small, pointed, and more or less adpressed, spinelet, directed upward and outward, and 
scarcely noticeable without a magniying glass. Up to the middle of the ray this spinelet 
may be accompanied by one or two much smaller microscopic spinelets, usually placed 
above it, and with a tendency to form a small compact vertical series or comb, adpressed 
to the ray, on the upper part of the plate near the aboral margin. 
The adambulacral plates are elongate, but also rather broad on the inner half of the 
ray, and the margin towards the furrow is convex. Their armature consists of :—(1.) A 
furrow series of five or six small but rather long, cylindrical, obtusely tipped, delicate 
spinelets, which radiate slightly apart and form a fan over the furrow. (2.) The actinal 
