JAPANESE ASTEEOEDEA. 141 



slender, and those next the mouth more robust, than the rest, 

 although the more robust ones near the mouth are not so pro- 

 minently different from the others as in some other species. In 

 smaller specimens however, the few spines at the mouth end are 

 much longer than the others and form an oral armature. In 

 addition there may be two or three very small, almost capillary 

 spines in the distal part of the main ridge, on the furrow side. 



Ventrolaterals. — The actinal interambulacral area is very 

 small, and the ventrolateral plates are also very small, there 

 being only 2 or 3 one either side of the interradial line (PI. Ill, 

 fig. 36). 



Paxillce. — At the middle of the arm the paxillar area is 

 mostly twice or more as wide as the superomarginals of one 

 side ; but it is subject to considerable variation, and in some 

 examples it is only about as broad as the superomarginals. The 

 paxillsB are of various sizes in different parts of the abactmal 

 surface (PL III, 41). At and near the centre they are always 

 smaller and form here a circular area of a different external 

 appearance from the surrounding parts but passing on to them 

 without any demarkation. This part is sometimes elevated into 

 a conical prominence. The paxillae are also small along the 

 superomarginals and bear only a few coronal spinules, presenting 

 a certain external resemblance to the pedicellariœ. The paxillae 

 are largest at about the middle of the base of the arm, and in 

 these there are as many as 10 or even up to 15 central blunt 

 spinules surrounded by some 15 peripherals which are smaller. 

 In some of the smaller paxillas from the centre of the disk, there 

 may be only one central and about 8 or 10 peripherals. The 

 pedicel of the paxillae is flattened from side to side ; the base and 



