NEW FOSSILS OF THE COKNIFEEOtJS FORMATION BARRIS. 283 



ble. It differs mainly in having no appreciable anal area, and but two 

 radials. 



The following diagram illustrates the structure of the body to the sum- 

 mit of the brachial plates : 



^&^^ 



Stereocrinus triangulatus (n. sp.)- 



Plate xi, figs. 1 and 2. 



Body large ; breadth to height as two to one. Basal pieces solidly an- 

 chylosed, and either as a narrow rim clings closely to the column or 

 widens into a pentagon, on each side of which rests the first radial. 

 First radials large, hexagonal, the centers of which are connected to- 

 gether by ridges, forming a pentagon, whose sides are parallel to those 

 of the anchylosed basal plate. Second radials pentagonal, nearly the 

 size of the first radial. First supraradials about half the size of the 

 second radial, pentagonal or hexagonal, resting mainly on the sloping 

 upper side of the second radial, and partly on the interradial, broader 

 than high. The second supraradial, or rather brachial, is of irregular 

 triangular shape, broader than high, whose base is nearly the breadth of 

 the supraradial. First interradial large as first radial, heptagonal, higher 

 than broad. This sustains a second interradial hexagonal, not more than 

 half the size of the first. This is crowned by three small irregular 

 plates, arching from arm to arm, surmounted by another series of three, 

 somewhat smaller. The summit is elevated in the centre, From each 

 series of arms, extending towards the center, is a ridge of larger plates. 



