British Fossil Crinoids. 393 



post. B, 4 nun. Post. B rises above the level of the otlni- 

 BB, and continues the outward slope of the cup ; its upper 

 margin, seen from the side or the back, is approximately 

 straight, but seen from above is boldly curved outwards. 



Ltll. All wider below than above, bending inwards so as 

 to give the cup its truncate globular shape. The facets do 

 not occupy the full width of the radials, and the shoulders of 

 the radials bend inwards between them, curving round the 

 facets. This feature is more marked in the r. and 1. post. EtR, 

 especially in the latter, where the radial rises up towards the 

 facet mote prominently than in the other rays. These two 

 posterior radials thus bend inwards round the rectal channel, 

 and approach within *5 mm. of one another at the shoulders; 

 their facets, however, are "9 mm. apart. 



Width Width Width of Height to 



below. above. facet. top of facet. 



mm. nun. mm. mm. 



Ant. R 3 ca. 22 ca. 1-8 3 



1. post. R .... 3 2-1 10 3-3 



The measurement " width above" is taken as near as may 

 be at the widest part of the facet ; thence the sides of the 

 radials converge towards the oral pole. The inward bend of 

 the radials cannot be properly represented in the analysis 

 (text-fig. 5). 



The outline of the facets is shown in text-fig. 2 ; they are 

 wider than deep. Their joint-face lies, as a rule, at right 

 angles to the long axis of the cup, but in the posterior 

 radials, especially 1. post. R, it slopes outwards a little, and 

 this is why the facets are more clearly seen in text-fig. 1 

 than in text-fig. 4. 



Each facet has a V-shaped ventral groove. There are 

 traces of a transverse fulcra! ridge in 1. post. R, but in the 

 others the surface is too much worn for details to be made 

 out. The axial canal is not to be distinguished. 



In text-fig. 4 an attempt is made to indicate the relations 

 of the proximal region of the arms. It is fairly clear that 

 there were no definite interbrachials, and that any finely 

 plated perisome which may have connected the rays must 

 have been well towards the inner face. 



No anal plates are preserved, but their probable relations 

 are indicated in text-fig. 4, on the analogy with Taxocrxnus. 

 A narrow vertical series of curved plates probably rested on 

 the curved upper margin of post. B, and their edges were 

 probably connected with the incurved edges of the posterior 

 radials, and possibly with the lower part of the posterior 



