JAPANESE ASTEROIDEA. 243 



" Description, — Abactinal paxillar area compact ; paxillœ arranged in uot 

 very regular oblique transverse rows at sides of ray ; without order in 

 median radial area and centre of disk. PaxillfG largest at base of ray and 

 in iuterradial areas, decreasing conspicuously in size toward centre of disk 

 and tip of ray ; larger at sides of paxillar area tlian in midradial region. 

 Column of paxilla about as liigli as breadtli of base, flaring at summit, the 

 largest crowned with a coordinate floriform group of about forty-five short, 

 terete, often clavate, round-tipped spinelets ; of these about one-half form a 

 peripheral series and are a trifle slenderer and longer. On the smaller 

 paxilla3 the spinelets decrease markedly in size, but only slightlj' in number. 



" Abactinal plates in a prepared specimen, from inner or cœlomic side. 

 Plates small, closer together along midradial line and in centre of disk where 

 there are no papulee tlian at sides of area where papulœ are present. Plates 

 of latter region are circular in general shape, but nearly always more or less 

 irregular ; with four, five, or six short, abrupt, lobes iiTegular in length, 

 thickness and in distribution on the periphery of ^\sAß. These plates of 

 papular area are aiTanged in perceptible, although irregular, oblique trans- 

 verse rows (parallel with interradial line), usually six papulœ occur around 

 each plate (often five, and rarely foui") emerging between the irregular lobes 

 by which plates usually touch. Plates along median area of ray are even 

 less regular tlian others, and frequently there are no lobes at all. They are 

 shglitly smaller, and papulae are absent from a strip about four x^lates wide. 

 Toward centre of disk, plates decrease rapidly in size, become more crowd- 

 ed, and lobes if present are very inconspicuous and of irregular occm-rence. 

 The large primary interradial plate placed just adcentrally to the madi'epoiic 

 canal is convex internally (bears a large paxilla externally), and is slightly 

 concave on the outer edge, next to madi'eporic canal ; tlu'ee or fom* other 

 less regular and smaller plates complete the circle about the madi-eporic canal. 



" Superomarginal plates, fifteen in number from median inteiTadial line 

 to exti'emity of ray form an arched bevel to border of abactinal sm'face ; 

 plates shorter than wide, but increase in length on outer half of ray. Plates 

 of both series separated by transverse naiTow deep fasciolar grooves and a 

 narrow deep gi-oove from inferomarginal series. Superomarginal plates 



