JAPANESE ASTEROIDEA. 



)99 



near the ambulacral furrows and the mouth there are small valvate 

 pedicellariœ (PL XVII, fig. 257, 258) ; they vary considerably 

 in number in the different specimens, but appear to be in general 

 more numerous in the specimens with more extensive fine-grained 

 areas. They also vary in form to a certain extent, some hav- 

 ing nearly square valves, while others are transversely elongated. 



The inner ambulacral spines are with very few exceptions five 

 in number and in one of the specimens the spines of the succes- 

 sive plates are imbricating, the adcentral spine or spines of one 

 plate being covered over on the furrow side by the abcentral 

 spines of the next adcentral plate. The spines of the mouth- 

 plates are either seven or eight for each plate, of which the one 

 at the mouth end is wedge-shaped when viewed from the actinal 

 side ; this spine may be subequal in size to its fellow of the 

 other side, or it may so far surpass it as to bring about the 

 appearance of an unpaired spine at the mouth end. The outer 

 ambulacral spines are two in number and one of them is con- 

 siderably smaller than the other ; both are rounded conical in 

 form. The outer spines of the mouth plates are the direct con- 

 tinuations of those of the adambulacral plates, and may vary 

 from five to eight for one interradius. 



The dimensions of these three specimens are as follows : 



A fourth specimen, also full-grown, is in a very good state 

 of preservation in alcohol. It is subglobular in shape, being dis- 



