300 s. goto: 



than their surroundings. In such cases the pedicellariœ are as a 

 rule larger towards the margin of the ray. 



The armature of the adambulacral plates varies somewhat. 

 The first two plates rarely bear pedicellariœ, and the number of 

 large spines is usually four or five ; in the following few plates 

 the number of large spines may be three or four, and the pedicel- 

 lariœ may be absent ; but in the greater part of the arms, the typi- 

 cal arrangement of the spines and pedicellariœ described by 

 Sladen obtains (PI. VII, figs. 107, 110). In the outer half of the 

 arms the adambulacral pedicellariœ are frequently wanting. 



The mouth-plates bear at the mouth end more usually two 

 pairs of forficiform pedicellariœ than one (PI. VII, fig. 106, 109). 

 Each mouth-plate bears on the actinal ridge a series of six or 

 seven larger spines, and a second series of five or six similar 

 spines parallel to the first ; the rest of the plate is covered with 

 a number of smaller spines without any regular arrangement. 



The madreporite is completely hidden from view by the sur- 

 rounding paxillœ, and is situated at the margin of the disk, the 

 outer margins of the disk and plate coinciding with each other. 

 It is perfectly flat and irregular in outline owing to the encroach- 

 ment of the adjacent paxillœ ; it may also bear a paxilla (PI. 

 VII, fig. 112). 



Localitij.— This species is the commonest Luldia on the coasts 

 of the Main Island but appears to be less common in Hokkaido. 

 I have specimens from Volcano Bay, Misaki, Bay of Tokyo, 

 Gulf of Suruga, Gulf of Isé, the Inland Sea, Gulf of Kagoshima, 

 and Miyazu and Namerikawa on the side of the Japan Sea. 



Specimens in S.C, H.N.S., H.N.S.W., S., I.M., F.B. 



