REPORT ON THE ASTEROIDEA. 641 
9. Freyella benthophila, n. sp. (Pl. CXI. figs. 5-8). 
Rays six. R= 88mm.;7r=3 mm. R = 30 7, approximately. Breadth of a ray 
at the base, 2°5 mm. ; at 10 mm, from the disk, 1°75 mm.; and at about midway between 
the base and the extremity, 1 mm. 
Rays very long, extremely delicate and attenuate, cylindrical at the base, very slightly 
inflated in the ovarial regions, which extend about 10 mm. from the disk, or occupy the 
proximal ninth of the ray; beyond this the ray is subtriangular with a truncate carination, 
and tapers continuously to a very attenuate extremity. The interbrachial arcs, though 
sharply rounded, have somewhat of an angular character. 
The disk is small, with the abactinal surface slightly subconically convex, and higher 
than the abactinal surface of the rays, the outline when seen in profile passing with a 
gentle slope towards and along the ray, the interference of the ovarial inflation being very 
slight. The abactinal area of the disk and of the ovarial regions is covered with very 
delicate calcareous plates overlaid with extremely delicate membrane. The plates bear 
two or three short, rather stumpy but very minute, spinelets (quite microscopic), and a 
number of small distributed pedicellarie, the whole having more or less of a grouped 
appearance on each plate. On the outer part of the ovarial regions the microscopic 
spinelets frequently appear to be less numerous. The plating does not extend beyond 
the ovarial region, and from thence to the extremity the abactinal surface of the ray is 
covered with an extremely delicate semitransparent membrane. Small pedicellariz are 
distributed over the membrane and, though numerous, have a comparatively widely spaced 
appearance ; they are most numerous towards the lateral margin, and may to a certain 
extent be said to occur in patches corresponding to the “ vertebra” of the ray, but do not 
approach the character of the aggregated groups on the saddle-like sacculi noticed in 
other species. 
The ambulacral furrow is broad and occupies nearly the whole of the actinal surface 
of the ray, the adambulacral plates forming only a narrow margin; its width is about 
1 mm. where the ray is 175mm. The adambulacral plates are elongate, 1°3 mm. in length 
at 10 to12 mm. from the disk, and measure the same quite close to the extremity, where 
the length appears relatively greatly emphasised in consequence of their narrowness and 
attenuation. ‘he plates are very narrow midway between their extremities, their outline 
being distinctly concave; the furrow-margin is the most incurved, and the outline of 
the furrow has consequently the appearance of a lineal series of confluent ovals. The 
armature of the adambulacral -plates consists of a single very delicate spine articulated on 
a small tubercular prominence on the middle of the actinal surface midway between the 
extremities, and an equally delicate lateral spine, often of the same length but normally 
slightly longer, articulated on a rudimentary infero-marginal plate ankylosed on the lateral 
wall immediately beneath the spine just mentioned, usually on alternate plates, but some- 
times less frequently. These spines are enclosed in delicate membranous sheaths with 
(ZOOL. CHALL, EXP.—PART L1.—1888.) 81 
