CALAMOClilNUS DIOMEDJ^. 



The Calyx. 



The five basals are pentagonal, joining by their long sides ; the lower 

 side of the basal in contact with the upper stem joint is slightly longer 

 than each of the upper sides of the basiradial faces. (Plate II. Figs. 1, 2; 

 Plate III. Figs. 1-3.) 



The basals are nearly four fifths the height of the primary radials. The 

 diameter of the basal ring at its junction with the stem is about half that 

 of the basal ring at its junction with the radials. The outline of the basal 

 cup seen in profile bulges slightly above its junction with the stem, then 

 forms a slightly re-entering curve, to bulge out again at the junction of the 

 radials, with a second re-entering curve in the middle part of the radials. 

 (See same figures as above.) 



The radials are elongate, deeply cut into by the first brachials, which cut 

 out a circular sector extending nearly one third the height of the radial. 

 The vertical sides of the radials flare slightly and the diameter of the calyx 

 gradually increases to the eighth brachial. (Plate IT. Figs. .1, 2 ; Plate III. 

 Figs. 1-3.) 



The first brachials do not occupy more than two thirds of the distal edge 

 of the radials ; and the deep cut made into the first radials by the first 

 brachials leaves two comparatively short sides of adjoining radials, which 

 separate the first brachials, and are in contact with the rows of heavy im- 

 perforate plates forming the proximal part of the perisomic plating. (See 

 same figures as above.) 



There is a marked asymmetry in the primary radials which abut against 

 the plating forming the base of the anal proboscis. They are somewhat 

 longer than those of which the sutures face the other interradiu (Plate II. 

 Fig. 2.) 



