JAPANESE ASTEROroEA. 425 



and separated from the farrow series of spines by a furrow is a 

 flattened, spatulate spine, similar in shape to those of the infero- 

 marginal series but shorter, and usually turned away from the 

 furrow. Occasionally this spine is doubled or even trebled (PI. 

 XIIT, fig. 213) and in such cases the individual spines are smaller 

 than when there is only one. Beginning with the second 

 adambulacral plate, there is a forcipiform pedicellaria at the 

 adcentral end of each plate in the longitudinal groove separating 

 the furrow series of spines from the spatulate ones (PI. XIII, fig. 

 213, 214). Occasionally it is curved towards one side, but usually 

 it is straight. From near the base of the arms on the adam- 

 bulacral plates are in direct contact with the inferomarginal series. 



Mouth-plates. — Viewed from the actinal side each mouth- 

 plate is triangular in form, apposed to its fellow by its longest 

 side and facing the first adambulacral plate by its shortest. On 

 the furrow border of the plate there is a compact series of 7-9 

 stout, flattened, somewhat wedge-shaped spines (PI. XIII, fig. 212). 

 On the actinal surface, close to the furrow series, there are on 

 each plate one to three stout spines similar in general form to the 

 outer spines of the adambulacral plates but usually less stout. 

 The rest of the actinal surface of the mouth-plates is covered over 

 with flattened, rounded, polygonal granules, which are much coarser 

 than those of the ventrolaterals. 



Ventrolaterals. — The ventrolateral plates are well developed 

 and very conspicuous. There are nearly forty of them in each 

 interradius ; the individual plates are irregularly polygonal and 

 those near the inferomarginal series are smaller than the more ad- 

 central ones, those in contact with the adambulacral plates forming 

 a distinct V-shaped series in each interradius ; a second similarly 



