30 University Geological Survey of Kansas. 



uinu, deeply concave and superior to the basals, forming a 

 large elevation in the interior of the cup, nearly one-fourth its 

 entire width and fully one-half its height ; column round, com- 

 posed of thin plates, which are carinated, and the sutures are 

 crenulated ; the canal is round and small. Basals five, large, 

 tumid, three hexagonal and two heptagonal, unequal, situated 

 below the infrabasals and forming a large part of the real body 

 cavity of the cup. The three anterior basals are equal, about 

 as broad as high, very convex, the posterior one compressed 

 laterally, superior lateral edges longer than the others ; trun- 

 cated side for the support of interradial short, side next the 

 radianal long ; the right posterior basal heptagonal very broad, 

 left posterior side very long, side adjacent for the reception of 

 the radianal very short, the latter being situated between the 

 posterior basal and the right posterior radial. Radials five, 

 large, very moderately ascending, placed superior to the basals, 

 five- to seven-sided, quite massive, more than twice as large as 

 the basals, convex, twice as wide as high, upper exterior por- 

 tion much beveled and concave ; plates separated at the corners 

 and often along the line of union ; at the upper union there 

 seems to be an opening that communicates with the calyx cav- 

 ity between the arms ; right and left posterior radials forced 

 apart fully one-half the diameter of either by the interradial 

 and radianal ; the upper surface is faceted the entire width of 

 the plate, two external ridges present and milled ; the remainder 

 of the surface is nearly flat or a little concave ; the plane of 

 these surfaces is not horizontal but the inner side of each is 

 higher than the outside, so that if each were produced inward 

 they would form rather an obtuse cone ; the inner notch occu- 

 pies about a third of the upper surface of the plate. Radianal 

 long, coffin-shaped, curving upward above, about twice as long 

 as wide, pentagonal, side adjacent to the right radial much the 

 longer ; the superior side supports an anal which is hexagonal, 

 very thick, six-faceted above, touching right radial for a short 

 distance, one and one-half times as high as wide, widest above, 

 mostly without the calyx. Anal large, heptagonal, very thick, 



