40 " ENDEAVOUR SCIENTIFIC RESULTS. 



asymmetrical ; they occasionally replace one or more of the 

 marginal granules. Papulae numerous, small, single, occurring 

 scattered more or less irregularly among the plates ; occasion- 

 ally a regular series of 6 surrounds a large plate. Madreporite 

 small, about equal to 2 or 3 ordinary abactinal plates, rounded 

 triangular, only half as far from centre of disk as from disk 

 margin. 



Superomarginal plates about 40 on each side of each ray 

 (48 in the largest specimen), those in interradial region nearly 

 twice as wide as long, more nearly square at middle of arm and 

 then becoming much wider than long again near tip ; all are 

 closely covered with granules, similar to but more rounded, and 

 the marginal ones at least, distinctly coarser, than those on the 

 largest abactinal plates ; there are about 100 on each of the 

 superomarginals near the interradius ; occasionally pedi- 

 cellarise replace granules. Terminal plates small, distinctly 

 longer than wide, not deeply notched distally. Infero 

 marginals apparently one less on each side of each ray than 

 superomarginals, at least in the larger specimens ; the number 

 may be the same in the two series, but in many cases the series 

 do not correspond exactly along the middle of the arm ; the 

 granular covering of the inferomarginals is hke that of the 

 other series. Actinolateral plates in 8-9 series ; the first 

 (adjoining the adambulacrals) extends from the oral plates to 

 the tenth inferomarginal from the tip of the arm ; the next 

 series extends to the twentieth inferomarginal from arm-tip ; 

 the next series only reaches the eighth or ninth inferomarginal, 

 counting from interradial mid-line ; remaining series irregular 

 and of few small plates ; all the plates carry coarse, angular 

 granules like those on the abactinal plates, but no pedicellarise 

 occur ; at least I have seen none. Adambulacral plates 

 squarish or rather wider than long, about 60 (in the holotype), 

 the inner margin at first straight but becoming decidedly convex 

 distally ; furrow margin with a series of 5 or 6 flat, blunt 

 spines, rather crowded, nearly equal or the most adoral 

 shortest (in the figure [Fig. 3 J the spines are too abruptly 

 truncate and are too widely spaced) ; externally is a second series 

 of 4 shorter, thicker, more angular spines ; a third series of 3 or 4 

 still shorter and thicker spines are borne on the outer margin 

 of the plate ; between this series and the second is a rather 

 conspicuous bare space ; the spines of the third series are 

 scarcely to be distinguished from the angular granules on the 

 actinolateral plates. Oral plates neither conspicuous nor 

 peculiar ; the oral spines, especially at tip of jaw, are, however, 

 svery heavy, more or less prismatic and 2-3 mm. long. Colour, 



