REPORT ON THE ASTEBOEDEA. 455 



superior series are scarcely distinguishable from the paxillse of the abactinal surface 

 generally. 



The adarnbulacral plates are large, aud their armature consists of two series of spines. 

 (1.) A furrow series of four or five short, flat, lanceolate spinelets, each in a membranous 

 sac, which radiate apart and form a fan on the furrow margin of the plate. (2.) An 

 actinal series of four or five large robust spines arranged in a straight line on the actinal 

 surface of the plate at right angles to the furrow. These spinelets are thickly covered 

 with membrane, and normally decrease in size as they recede from the furrow. The 

 general surface of the plate is covered with membrane. 



The mouth-plates are moderately large. Their armature consists of a marginal series 

 of about nine spinelets on each plate, the innermost three on each plate being much 

 larger than the succeeding ones, and enveloped in wide membranous sacs, which give them 

 a compressed lanceolate appearance ; the outer spinelets are much smaller, subconical or 

 cylindrical in appearance, and diminish in size as they recede from the mouth. On the 

 actinal surface of each plate is a lineal series, parallel to the median suture, of five robust 

 sacculated spines which diminish in size as they recede from the mouth, the innermost 

 being larger than any of the other mouth-spines. 



In the actinal interradial areas of the disk there are three or four series of small actinal 

 intermediate plates, which bear small, compact, well-defined paxilliforrn groups of four 

 to six short ecpial spinelets ; only the innermost of these series extends more than a little 

 way beyond the base of the ray. 



The madreporiform body is small, and is situated rather nearer the centre of the disk 

 than midway between that point and the margin. Its surface is slightly convex, and 

 the striations are fine. 



The ambulacral tube-feet have large, fleshy, centrally-invaginated, terminal disks. 



Colour in alcohol, a bleached grejdsh white. 



Locality. — Station 308. South of Wellington Island, west - coast of Patagonia. 

 January 5, 1876. Lat. 50° 8' 30" S., long. 74° 41' 0" W. Depth 175 fathoms. Blue 

 mud. Surface temperature 51 0, 7 Fahr. 



Remarks. — Solaster regularis is characterised by the length of the rays, and by the 

 comparatively large and widely-spaced paxillae of the abactinal surface : characters which, 

 taken in conjunction with the number of the rays and other minor points of detail, at once 

 distinguish the species from its allies. 



4. Solaster subarciiatus, n. sp. (PL LXX. fig. 2 ; PL LXXII. figs. 7 and 8). 



Rays nine. E= 38 mm. ; r= 12 mm. R>3 r. Breadth of a ray at the base, about 

 7 mm. or rather less. 



The rays are moderately elongate, and taper only slightly on the inner half of their 

 length, but more rapidly on their outer half, remaining, however, rather broad even to 



