134 ART. 2. — H. MATSÜMOTO : 



stout, obtuse tubercles, which are larger and more numerous on 

 the radial shields. Radial shields also covered by the skin, long, 

 narrow, strongly raised, about two-thirds as long as the disk 

 radius. Inter brachial ventral surfaces covered by a skin similar 

 to that of the dorsal surface, the granules and tubercles being 

 however smaller. Genital slits large, long, but not reaching the 

 disk margin. 



Oral skeleton also covered by the cereous skin. Oral shields 

 rather small, thick, rhomboidal, wider than long, with wide, 

 rounded outer angle and convex surface. Adorai shields large, 

 quadrangular, with perfectly rounded outer angles and strongly 

 convex surface, wider without than within, meeting wdth each 

 other inwards. Between each pair of oral plates, occurs a more 

 or less distinct buccal pore. Three or sometimes four oral papillae 

 on either side, conical and blunt ; inner ones smaller ; the outer- 

 most papilla is very large and stout. There occurs often one 

 additional papilla just below the teeth. The oral papillae project 

 laterally so as to reach beyond the radial axis, and those of the 

 two sides of each oral slit are placed alternately. Teeth conical, 

 stout, obtuse. 



Arms slender, covered by a thin, cereous skin. Dorsal arm 

 plates two to each joint ; the inner one has convex surface, and 

 is small, quadrangular, wider than long, but in the more distal 

 part of the arm is often longer than wide ; the outer one is 

 large, fan-shaped, much wider without than within, and has 

 convex surface. The dorsal side of the basal region of the arms 

 is covered by the continuation of the disk covering, so that it 

 bears coarse, rounded, smooth, convex, well spaced granules or 

 scales of various size in place of the dorsal arm plates. Lateral 

 arm plates somewhat flared outwards, meeting below for a short 



