NO. 1793. NEW STALKED CRINOID FROM THE EAST INDIES— CLARE. 475 



The joint faces in the upper middle portion of the stem (which is 

 in two pieces) are marked with radial crenellse, but there is a plane 

 area about the central canal, equal in average width to half the 

 diameter of the canal, which is produced into six angles whose apices 

 reach halfway to the periphery of the joint face, or even somewhat 

 farther. 



One of the six angles of the stem is exactly in radius D. 



On the topmost three or four columnars supplementary tubercles 

 are formed between those occurring from radius A to radius C. 



Basals. — The basals are three in number, but so closely united 

 that the sutures are almost obsolete; one of the basals supports the 

 anterior radial; the division between the two others coincides with 

 the suture between the radials on either side of the anal interradius. 



The basal cone is approximately 2 mm. high (radially), 3.5 mm. 

 in distal and 2.5 in proximal diameter; in its proximal third its sides 

 are parallel with the dorso-ventral axis, and bear six prominent 

 though well-rounded tubercles, two to each basal; in the distal two- 

 thirds the sides diverge at an angle of about 68°, and there are five 

 shallow interradial depressions. 



Radials.— TYiQ radials are roughly pentagonal in shape ; the sutures 

 between them may be easily seen, though the union is very close; 

 each radial is about 2.2 mm. wide at the base, 4 mm. wide distally, 

 3.7 mm. liigh interradially, and 3.5 mm. high to the base of the first 

 brachial; the socket serving for the attachment of the first bracliial 

 is only about 1.7 mm. broad, so that not much more than one-third 

 of the distal margin of the radial is occupied by the articulation; 

 the free interradial borders are turned upward and then slightly 

 inward; in profile the sides of the radial circlet are seen to make an 

 angle of about 68° with each other; the middle line of the radials is 

 occupied by three nearly obsolete tubercles, a pair proximally (one 

 on either side of the midradial line) and a single one just proximal 

 to the articular socket. The border of the radials (and basals also) 

 along the interradial and basiradial sutures is usually narrowly 

 depressed, so that these sutures appear in depressed bands. 



Tegmen. — The tegmen is a rather high five-sided pyramid, the 

 apex (the apices of the orals) being 5 mm. above the interradial 

 margin of the radials, or about as high as the base of the sixth 

 brachial; each ambulacrum is raised high above the general surface 

 of the tegmen upon a narrow wall, the crest of which at first runs 

 outward horizontally from the base of the orals and then curves up- 

 ward, merging into the ambulacrum of the arms at about the sixth 

 brachial. 



The orals are very large, reaching nearly two-thirds of the distance 

 from the tip of the oral pyramid to the interradial border of the 

 radials; in their inner half they resemble the orals of Hyocrinus, 



