ASTEROIDEA OF H.M.S. ' CHALLElirGER ' EXPEDITION. 261 



functions. On the outer portion of the second adambulacral 

 plate there is a partial repetition of tMs arrangement. 



The paxillar area is wide and extensive, with numerous rather 

 small compact paxillse. The spinelets of whict these are com- 

 posed are short and uniform. The larger paxillge have a circlet 

 of 12-14 spinelets surrounding 7 or 8 on the centre of the 

 tabulum ; and the smaller paxillse present about half those num- 

 bers. Along the sides of the rays the paxillse are arranged in 

 regular transverse lines about 5 or 6 in each. The paxillge dimi- 

 nish greatly in size in the neighbourhood of the centre of tbe disk 

 and towards tbe ends of the rays. 



The madreporiform body is small but tubercular, and is situated 

 nearer the margin than midway to the centre. 



The terminal plate is moderately large and broad, and is deeply 

 grooved at the extremity. 



Colour, in alcohol, yellowish wMte. 



Station. Simon's Bay, Cape of Grood Hope. Shallow water ; 

 5-20 fms. 



ASTROPECTEN ZEBRA, n. Sp. 



Rays five. i2=3"7r; ^=34 millim., r=9millim. Eays rather 

 narrow, and although tapering gradually from the base to the 

 extremity, the tip is comparatively obtuse. Breadth of a ray 

 at the base about 9 millim. Interbrachial angles distinctly 

 rounded. 



Sup ero -marginal plates 25 in number from the interbrachial 

 angle to the extremity, higher than broad, and having the ap- 

 pearance of forming a rounded sloping bevel to the ray, especially 

 in the arm-angle. The plates are uniformly covered with papil- 

 liform granules, and bear no spines or tubercles whatever, ex- 

 cepting the four innermost plates on either side of the median 

 interbrachial line. These four or five plates are armed with a 

 short, conical, and slightly compressed spinelet, the innermost 

 being longest and the others decreasing in size as they proceed 

 outward. 



Infero-marginal plates much broader than high, and do not 

 extend beyond the superior series, although in large specimens 

 there is a tendency to appear to do so in consequence of the 

 presence of a slight prominence on the plate on which the mar- 

 ginal spine is articulated. One marginal spine of moderate length, 

 taper throughout and sharply pointed, cylindrical, very slightly 



