128 



NEW YORK STATE MUSEUM 



with numerous small shallow pits scattered between. Each sup- 

 ports at its apex two very nearly equal interradial plates with 

 usually a vertical suture between them. 



First brachials about 2.5 mm wide and nearly square. The outer 



,._jFig. 7 Analysis ofHercocrinus ornatus. Note that the radials instead of being 

 "separated by a single distinct plate" are separated quite regularly by a pair of nearly equal 

 interradial plates. The depressed plate boundaries and raisedridges have been but roughly 

 indicated. The interradial area to the left of the upper one is the area shown in plate lo. 

 Two depressions across the top of the central plate of this area are strongly indicative of 

 sutures and one of these is represented in part by a dotted line. The photograph made the 

 depressions appear as sutures a-nd they were so drawn for plate lo. The angles of the sur- 

 rounding plates in this figure would suggest that the arrangement of plate lo is the correct 

 one. The fine line of the suture itself is often hard to detect. 



prominent transverse ridge of the basals is continued along the 

 edges of the radials and brachials and over the outer edge of II Br^. 

 The whole ridge forms an almost complete, raised boundary about 

 .6 mm outside the edges of the circular or slightly oval interradial 



