NO. 4 ziesenhenne: new eastern pacific sea stars 199 



Inferomarginal plates 20, of the usual form, about as wide as length 

 of three plates interradially, whence the width rapidly diminishes toward 

 end of ray. The outer end of the first two plates is narrower than the 

 inner. The outer end of the plates, forming the rounded ventrolateral 

 border of the ray, is closely covered with rather truncated capitate spine- 

 lets similar to those of the superomarginals (but projecting a little farther 

 outward) ; but on the actinal surface these become slenderer, clavate, 

 with the thorny ends sometimes obliquely pressed, or bent, toward mar- 

 gin of ray. There are no enlarged tubercles on any marginal plate. 



Actinal interradial areas small, comprising 2 complete chevrons of 

 plates. The inner chevron, without an odd interradial, extends to fourth 

 inferomarginal; the second, with a conspicuous unpaired interradial, 

 reaches to the second plate, while outside the odd plate are two others 

 indicating a third and fourth chevron to come. The plates have a low 

 tabulum, carrying a few capitate spinelets, like those on outer end of 

 inferomarginals, and also usually a few slender clavate ones. 



Adambulacral plates 26, with an angular furrow margin, a convex 

 surface, and somewhat sunken transverse sutures. The first few plates 

 are wider than long, but they continue to narrow distally until on outer 

 third of ray they are longer than wide. Furrow spines proximally 4, but 

 over most of ray 3, subspatulate, blunt, the median member with edge to 

 furrow. There are proximally 9 or 10, distally about 6, clavate, thorny 

 subambulacral spinelets a little smaller than the furrow members, ar- 

 ranged in about 3 longiseries proximally and 2 distally. The distal mem- 

 ber of the longiseries often stands on the furrow margin and can reason- 

 ably be counted as a fourth or fifth furrow spinelet. 



Mouth plates relatively large, the suture length about twice width of 

 combined plates. Furrow margin more than half suture length. Furrow 

 spines about 6, increasing in size toward apical spine, which is heavy, 

 clavate, and blunt. There are 10 or 12 suboral spinelets along margin of 

 median suture; 5 or 6 on margin adjacent to first adambulacral, and 4 

 or 5 scattered in between. 



Madreporite oval, convex, diameter 1.25 mm., raised above disk 

 plates, located in the median interradial area along the superomarginals. 

 Striations coarse, irregular, centrifugal, arched domelike. IVIadreporite 

 surrounded by 6 large paxillae, which often conceal it. 



Color. — Dried, actinal surface is cream bulif, abactinal surface and 

 marginals yellow cream buff. 



Holotype. — AHF no. 44; 7 paratypes. 



