142 ART. 2. — H. MATSUMOTO : 



small, intervening scales, and bear several very prominent, spherical 

 tubercles along the outer margins. Radial shields very large and 

 stout, triangular, with an acute inner angle, longer than wide, 

 each pair in contact by the outer half of their whole length, and 

 narrowly separated from the next pair by a sunken, oblong plate. 

 The radial shields do not lie in the same plane with the central 

 rosette, but are inclined outwards and interradially, so that the 

 central rosette appears elevated above its surroundings. The 

 radial sliields also bear prominent tubercles along or on their 

 adradial borders, as well as often along their outer margins. Just 

 outside and below the outer edge of the radial shields, there is a 

 very stout and nearly vertical plate, on which the radial shields 

 rest elevated above the general surface of the arm. Interbrachial 

 spaces below very small, covered by a few convex plates. Genital 

 slits small, lying just outside the oral shields. 



Oral shields large, rhomboidal, wider than long in surface 

 view, but the outer angle is prolonged upwards like a beak. 

 Adorai shields longer than the oral shields, wider without, tapered 

 inwards and meeting each other. Three oral papillae on either 

 side, rather close-set, outermost one quadrangular, largest of all, 

 wider than long ; the next bluntly and the last acutely pointed, 

 both being longer than wide. Four or five teeth, stout, spear- 

 head-shaped, the uppermost one longer and acuter than the rest. 



Arms stout and sliort, uniformly tapered outwards. Dorsal 

 arm plates triangular, with straight inner sides and two-lobed 

 outer, wider than long, strongly convex, separated from one another 

 by the lateral arm plates, which are very stout and strong- 

 ly flared outwards. First ventral arm plate small, pentagonal, 

 longer than wide, wider within than without, if we except 

 the pointed portion. Second and following triangular, with concave 



