176 



AET. 2. — H. MATSÜMOTO 



imbricating scales, which are finer outwards and along the sides 

 of the radial shields. Primary plates indistinct. Radial shields 

 long and narrow, acutely pointed within, about one-fifth as long as 

 the disk diameter, meeting with each other for nearly their whole 



length but parted at 

 the proximal end. 

 Interbrachial ventral 

 surfaces covered also 

 with imbricating 

 scales, which are 

 somewhat finer than 

 those of the dorsal 

 surface. Genital slits 

 long. 



Oral shields 

 ovate, or rather 

 triangular with per- 

 fectly rounded 

 angles, lateral sides 

 quite and outer side 

 strongly convex ; 

 much longer than 

 wide. Adorai shields 

 triangular, tapered 

 within to a point, 

 where they nearly meet. The apical oral papillae are oval and 

 stout. Two distal oral papillae on either side ; the outer one is 

 the largest of all, much wider than long, flat, thick, has curved 

 free edge, and arises from the adorai shield ; the other longer than 

 wide, flat, thick, with obtuse end. Besides, there occur above the 



Fig. 4S. Amphlchilus trichoides. x20. a. From above, h 

 From below, c. Side view of three arm joints near disk. 



