Benham. — Sttilertds (iiid Kchiii,nh from flu' hi'rtnaders. 



143 



These are the primary iiiterradials. Each presents 5 lobes proximally 

 and a h\rge single or feebly notched lobe distally. From the latter a series 

 of paired plates lying side by side pass outwards to the interbrachial margin. 

 At intervals along this double row there are semi-stellate plates with radiat- 

 ing rods on either side (fig. 2). 



Outside the interradials is a series of 5 primary radials at the base 

 of the rays. Each is a more or less rosette-shaped plate with 5 to 7 lobes. 

 Along the middle of the ray is a series of similar plates connected together 

 by short rods, which in the distal region of the arm become shorter and 

 shorter, so that the median rosettes come to lie closer together (fig. 2). 



Along each side of the radials or median row is a lateral series of similar 

 rosette plates, but of less size ; these, however, cease about half-way 

 along the arm. They are connected to the median rosettes by short 

 narrow rods, and when the intermediates cease the rods become broader 

 and shorter, and connect the medians with the supra-marginals. Still 

 further out the radials themselves touch the marginals. 



The supra-marginals are large, irregularly oval or pyriform, or even 

 subtriangular. with rounded angles ; they are very convex outwards, and 

 are obliquely placed and loosely articulated. I find 11 or 12 along each 

 side. 



The infra-marginals have the same general form, but are rather smaller, 

 with the longer axis longitudinal ; and, though usually immediately below 

 the supra-marginals, the number is lather greater — 12 or 13 (fig. 3). 



On the upper surface there are the characteristic " valvate pedicel- 

 lariae " at the base of each. arm ; they are of large size, measuring 4-5 mm. 

 in length. As Farquhar has noted, these are not quite regularly arranged 

 — not alM^ays paired — as will be seen from the following table (A and B 

 are large, C and D are young forms) : — 



