Blastoidocrinus carchariaedens Billings (sp.) 

 Page 97 



Figures a-f are of radials of different ages viewed from their bases and showing 



radiating grooves and marginal growth lines. 

 Figures g-h are of exterior surfaces of radials viewed in an inverted position. 



It is this surface that forms the inside of the craterlike hollow at the base. 

 Figure i shows the interior surface of a radial, the thick sutures where it 



meets the bibrachials and the larger interradials, and the narrowing at the 



suture to meet the smallest of the lower interradials. 

 Figures j-k are of radials seen from their edges ; j has a vertical ridge on the 



interior surface for the attachment of viscera, this ridge is not present in 



i and k. 

 Figures 1-n are of bibrachials ; 1 shows two as they join each other, m shows 



the interior surface and the remarkable widening of the face of the suture, 



n shows the exterior surface, and a deltoid suture with its transverse 



respiratory grooves. The last plate is of a less common form, i. e. is more 



acute at the apex. 

 The plates figured sho-^ some marked variation but all are from the same 



locality as the more complete specimen. They are now in the New York 



State Museum. 



