Indian Deep-sea Asteroidia. 85 



larlj placed, those on the rays in beautifully regular trans- 

 verse rows ; the whole abactinal surface closely perforated 

 with papula\ 



S^upero-niarginal plates 42, suj)erj)0sed on the infero- 

 niarginals, jjlate to plate ; almost entirely abactinal in jjosition ; 

 closely covered with nienibrane-clad granules, and bearing at 

 the actinad end each a stout procurrent spine. 



Infero-niarginal jjlates corresponding, plate to plate, with 

 the supero-niargiiials, covered with similar granules, and 

 armed with an obliquely vertical series of, usually, three stout 

 procurrent spines. 



The adanibulacral plates are practically within the furrow, 

 lying far below (/. e. above in the normal ]josition of the 

 animal in life) the level of the infero- marginals ; they are 

 distant inter se, and their slightly convex furrow-margin 

 bears a comb of, usually, six long needle-like spinelets, while 

 on the actinal surface there are two longitudinal rows of 

 inflated membrane-clad barleycorn spinelets. Mouth-plates 

 long and large, extremely tumid actinally ; each with a 

 furiow-series of seven or eight spinelets, the most central 

 (adoral) of which is of enormous relative size, with a suture- 

 series of ten or eleven spinelets, of which the most central is 

 enlarged, and with a few scattered granules between. 



i\ctinal interradial areas narrow, but long, the intermediate 

 plates reaching in a discontinuous series to the twenty-third 

 infero-niarginal, and those along the ray lying in a furrow 

 between the adambulacrals on the one side and the infero- 

 marginals on the other ; each plate with a clump of barley- 

 corn spinelets. 



Madreporiform plate small, somewhat concealed by paxillte ; 

 placed midway between margin and centre. 



Anus central, distinct, receiving the termination of a wide 

 intestine. 



Ambulacral groove of great width, its width being two 

 fifths that of the ray ; tube-feet very large, conical, in two 

 rows. 



Andaman Sea, 230 to 250 fathoms. 



This species is readily distinguished by the actinal hollowing 

 of the rays and by the flexibility of the disk. 



PSEUDARCHASTER, Sladcu. 



13. Pseudar chaster mosaicus, Alcock and Wood-Mason. 

 Pseudarchaster mosaicus, Ann. & Maj. Nat. Hist., Dec. 1801, p. 432. 

 Andaman Sea, 188 to 220 fathoms, green mud. 



