CLEIOCRINUS. 103 



plates are in place ; but it, as well as the interradially situate plates, is out- 

 side of the lower ring and outside of the column, projecting downward for 

 a distance of one to four columnars. Thus the ten plates forming the 

 proximal ring exteriorly, do not, except as to the upper angular points of 

 four interradials and one radial, enter into the interior of the calyx wall 

 proper, but are suspended on the outside of it. They appear out of place, 

 as if they might have accidentally slipped clown around the column. They 

 are rather thin, and are firmly grown to the outside of the true proximal 

 ring of plates, the angular points of four of the interradials and of the right 

 posterior radial rising slightly above their level. The first primibrachs are 

 exteriorly flush with the plates of the lower outer circlet, and rest upon 

 them, being sloped at the lower corners so as to fit the angles formed by 

 the upper points of the interradials, which are thus visible from the in- 

 terior. These first primibrachs also lie" directly above, but do not rest 

 upon, the plates of the inner circlet, not alternating with them but in direct 

 succession. The successive plates are all radial in position, without any 

 alternation whatever. Thus the five radially situate plates which rest upon 

 the column lie within the ten plates of the outer circlet, and meet them, not 

 by their upper or distal edges, but by their outer, or dorsal, surfaces. 



Now for the evidence of this : Referring to Plate I., Fig. 3 b shows the 

 specimen B from the right posterior side, with the lower circlet of radial 

 and interradial plates as seen from the exterior, and the first primibrachs 

 resting upon them and flush with them. The same thing can be seen in 

 Figs. 1 and 2, showing the two sides of the perfect calyx (Billings's 1 a and c). 

 Fig. 5a is from a photograph — enlarged two diameters by the camera, and 

 retouched with the brush — of the opposite, or left lateral, side of speci- 

 men B, after removal of the plates and debris covering the basal cavity, — 

 an obliquely interior view. All five of the large proximal, radially situate 

 plates are in plain view, with the large axial canal in the middle. Two 

 primibrachs and part of a third are in situ — in direct succession with the 

 last mentioned plates — and, at the right, the first plate of the anal series, 

 slightly displaced, resting upon the posterior interradial. Two of the radial 

 plates of the outer circlet are visible, one in the middle and one to the 

 right, with one of the interradial plates between them. The interradial to 

 the left has been removed, leaving the exterior face of the inner proximal 

 plate exposed, just as it rests upon the column. On the opposite side the 

 upper points of two of the interradials can be seen, between the lower 



