110 Mr. A. Alcock on 



third row of plates throughout the ray, and between the third 

 and fourth row of i)L^tos"in the basal fourth of the ray,_therc 

 are minute perforations (seen only in the dried specimen) 

 which appear to be too small for the passage of papute. 



Adanibulacral plates very small, but extending hig'h up 

 into the furrow ; each plate has two short transverse series of 

 spinelets, and every alternate plate has a prominent intra- 

 ambulacral ridge bearing three stout spinelets, of which the 

 innermost is furnished with a large pediceUaria emerging 

 from a cluster of small pedicellariai. Mouth-plates with long 

 needle-like spines and large clusters of pedicellaria3. 



Tube-feet quadriserial. 



Madreporiform plate very small, with coarse peach-stone 

 sculpturing. 



Colour in life orange-pink. 



Laccadivc Sea, 1043 fathoms, green mud. 



44. Zoroaster zea, sp. n. 



Eays 5. R = about 12 r. E,= 144 millim. in 

 the type specimen. 



Disk semicircular, flat-topped, well raised above the rays, 

 from which it is delimited by a circumferential series of 

 massive oval or substellate plates, arranged exactly as in 

 Z. Gilesii and Z. sguameus, with small plates intervening. 

 All the plates are quite smooth and membrane-clad, but the 

 small intervening plates bear each a small coarse spine ; the 

 intervals between the plates show distant papulce and pedi- 

 cellaria3, the last often hi pairs. 



Eays long, rigid, subcylindrical, tapering, with thirteen 

 longitudinal parallel series of Indian-corn-like or bead-like 

 membrane-clad plates, which also fall into transversely 

 parallel series. A single ray, viewed abactinally, has much 

 the appearance of a seed-spike of maize. The plates are 

 disposed as follows: — (i.) a mid-radial row of slightly 

 enlarged plates, flanked on each side by a deep furrow, in 

 which lies (ii.) a discontinuous row of minute platelets con- 

 cealed by membrane, and only revealed either by a small 

 pedicellaria or by a coarse spikelet which they sometimes 

 bear ; and outside these (iii.) six rows of plates, decreasing in 

 size and inclining to imbricate actinally, of which the three 

 abactinad rows are, like the mid-radial row, quite naked and 

 unarmed, while the three actinad rows are thickly covered 

 with membrane- clad squamous spinelets and bear a median 

 spine and sometimes a marginal pedicellaria. Long papula 



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