I32 FISHER 



each spinule for about half its length, leaving only its basal 

 part obscured. In consequence of the open character of skele- 

 ton, paxillse are well spaced, but are much smaller and more 

 numerous than in Crossaster papposus. They are largest and 

 most widely spaced midway between center of disk and margin 

 on radial areas, thence rapidly diminishing in size toward ex- 

 tremity of ray and less toward center of disk. A bare sulcus 

 leads from each interradial angle half way to center of disk. 

 These bare areas are about 1 mm. wide and are paved solidly 

 with ossicles which are the upper edge of the incomplete cal- 

 careous interbrachial partition. At the inner end of this bare 

 area, in 1 interradius is the madreporic body surrounded by 

 several paxillae ; in the other radii several slightly larger pax- 

 illae hold a similar position. Papulae large, partially obscuring 

 the small paxillae ; absent from bare interradial areas ; 2 to 7 or 

 8 to each mesh of skeleton on rays and as many as 15 on disk, 

 or even more where meshes are incomplete. Papulae com- 

 monly 3 mm. long, pointed. In the interradii a number of the 

 abactinal plates are actinal in position because the marginal 

 plates are drawn inward toward the mouth. Thus in the type 

 the distance between marginal plates and interradial angle is 6 

 to 8 mm., consequently the dorsal integument with plates and 

 papulae is drawn onto actinal surface. 



Marginal plates conspicuous ; about 14 or 15 prominent, 

 rather widely spaced, transversely oriented, paxilliform plates 

 seem to represent the inferomarginal series, and between each 

 of these, in the same linear series, are 1 to 3, usually 2, longi- 

 tudinally oriented, much lower and slightly smaller plates, 

 which may represent the superomarginal series, although now 

 forming a single series with inferomarginals. Prominent mar- 

 ginals become more conspicuous toward tip of ray, acquiring a 

 heavy, compressed pedicel often higher than its width at top, 

 and very paxilliform in appearance, bearing 2 transverse rows 

 of about 8 to 16 long, tapering needle-like spinules, which in- 

 crease in length but decrease in number toward extremity of 

 ray. Beyond proximal fourth of ray there are two well-de- 

 fined series of these spinules, of which the adoral spinules are 

 the shorter, and in the other series about 3 skin-covered spin- 



