JAPANESE ASTEROIDEA. 347 



ambulacral furrow, but they may also be more or less obliquely 

 placed or even nearly parallel to the furrow. They are similar 

 in shape to those on the adambulacral and abactinal plates, but 

 mostly larger ; rarely they may be 3-valvate (PI, XlII, fig. 209). 

 They form a row parallel to the ambulacral furrow and are very 

 conspicuous. In my specimen none of the outstanding ventro- 

 laterals bear pedicellariœ. The total number of ventrolateral 

 pedicellarioe in a single interradius is about 17. 



The ventrolateral plates with pedicellaria) next the adam- 

 bulacral plates bear each a single row of granules along the margin, 

 which is, however, usually incomplete on the inner border. All 

 the other ventrolateral plates are covered with granules, which 

 are unequal in size, but of which it is not possible to distinguish the 

 peripherals and centrals (PI. XIII, fig. 208). The granulation is 

 coarse as a whole, and the granules are generally coarser and 

 more rounded than those of the adambulacral plates. 



Abactinal plaies. — Of these we may broadly distinguish two 

 classes, the main and the interstitial plates, although it must be 

 distinctly understood that there is no sharp boundary between 

 them, and the distinction is made entii-ely for the sake of des- 

 cription. The main plates are of various size, but are generally 

 larger than the interstitial plates, and either bear a pedicellaria or 

 present a naked central area (PI. Xdl, fig. 207). They are circular 

 or elliptical in outline, and each plate bears a marginal row of small 

 granules. When there is no pedicellaria, the central area is entire- 

 ly naked and smooth, and is either level or elevated and mammiform. 

 When a pedicellaria is present it occupies the whole central 

 area. The pedicellariœ are transversely elongated and valvate 

 and are similar in form to those of the actinal side, except that 



