432 Messrs. J. Wood-Mason and A. Alcock on 



in transverse curved rows. The whole abactlnal surface per- 

 forated with close- set papulfe. 



The supero- marginal plates number about 28, and are 

 directly superposed on the infero-marginals, plate to plate ; 

 they are covered with granules, which are largest in the 

 middle of the plate, and are armed with rigid spines — those 

 in the interradia with one, those along the rays with one, two, 

 or three in a vertical series. The infero-marginals corre- 

 spond, plate to plate, with the supero-marginals ; they are 

 almost smooth in the middle and covered with papilliforni 

 granules round the edge, and are armed with from two to 

 four stout adpressed spines, situated in a median vertical series, 

 of which the most abactinal is the largest. 



Adambulacral plates with a strongly convex furrow-margin 

 which is armed with six or seven short, truncated, longitu- 

 dinally-grooved spinelets ; the actinal surface with two longi- 

 tudinal series of similar spinelets — about five in each series ; 

 these spinelets are almost clavate sometimes. Mouth-plates 

 small, very narrow, with widely open suture ; each phate with 

 a furrow-series of about ten small spinelets, the most adcentral 

 of which is much enlarged ; the actinal surface with eight or 

 nine truncated, longitudinally-grooved spinelets in a single 

 longitudinal series. 



Actinal interradial ai'cas large, the intermediate plates 

 extending much more than halfway along the ray ; in the 

 interradial areas each plate has a clump of from six to eight 

 truncated or clavate grooved spinelets ; along the rays the 

 intercalated plates have usually two longitudinal series of 

 similar spinelets — about four in each series. 



Madreporiform body small and inconspicuous or concealed, 

 situated about midway between the centre and the margin of 

 the disk. 



Ambulacral groove very broad and open ; tube-feet large, 

 conical. 



Colour in the fresh state "crushed-strawberry," sometimes 

 with a golden suffusion ; marginal plates pink, tube-feet 

 blood-red. 



Stations 107 and 109, 738 fathoms. 



PsEUDARCHASTEK, Sladen. 

 7. Pseudar chaster mosaicus^ sp. n. 

 Near P. tessellatus, Sladen. 



Rays 5. E. = 4 r. 

 Disk large ; rays tapering ; interbrachial arcs wide, rounded. 



