C54 



s. GOTO : 



.Vlong the margin of the arms there is a series of plates 

 probably corresponding to the iiiferomarginals, which are larger 

 than the adjoining plates of both the actinal and abactinal sides 

 and bear a larger number of minute spines (20 or more). 



Adamhulacral plates. — The adambulacral plates bear two 

 series of spines arranged in a curved fan-hke shajDO and each 

 series is connected together in the basal parts by a web dike mem- 

 brane, so that the individual spines are rather difficult to count 

 in alcohohc specimens. In the first series which directly faces the 

 furrow, there are (5 or 7 spines, of which the middle two or three 

 are larger than the others and either directly bounds or project 

 into the ambulacral furrow, the rest gradually diminishing in size 

 towards either side and borne more on the abcentral and adcentral 

 margins of the plates. On the actinal face of the adambulacral 

 plates there is a similar row of shorter spines, separated from the first 

 series by a groove (PL XTX, fig. 278). It may be remarked here 

 that the plates bearing this second yo\y of spines are regarded 

 by Dr. Batheb as distinct from tliose of the first series, hence the 

 apparent discrepancy between liis description and mine. The spines 

 of the second series are also connected together l^y a web -like 



