28 University Geological Survey of Kansas. 



composed of alternately thick and thin pieces, the outer half 

 of the sutures radially milled, the median canal of moderate 

 size. Basals large, three hexagonal, and the posterior and right 

 posterior ones heptagonal for the reception of the anals ; the 

 plates are nearly all equal, and the sutures are placed in a 

 shallow, rounded furrow, which in branching at the angles of 

 the plates gives them a rounded appearance, so that the plates 

 appear subsemicircular in outline. The radials are the largest 

 plates of the calyx, all pentagonal, all about equal, save the 

 right posterior, which is smaller than the rest ; the entire sur- 

 face truncated above, edge slightly beveled, wider than high, 

 entire upper surface faceted ; the transverse ridge is milled, the 

 lateral corners of the plates drawn in, apparently leaving a pore 

 which connected with the body cavity of the calyx ; there is a 

 dorsal canal piercing the upper surface of the plates ; the inner 

 edges of the plates are drawn in at the center and extend in the 

 form of a ridge to the canal. Costals 1x5, about half the size 

 of the radials, pentagonal, line of articulation with the radial 

 gaping, lateral edges constricted and apparently not in con- 

 tact, about twice as wide as high. The first interradial is large 

 and situated well down in the cup, supported by the posterior 

 basal and the one at its right, on the sides by the special anal 

 and the right posterior radial, and supports another anal above 

 it on its truncated top. The special anal is moderately large 

 and hexagonal, bounded on the right by the two interradials, 

 below by the truncated upper surface of the posterior basal, on 

 the left by the left posterior radial and the space between it and 

 the costal ; it is about half within the calyx. Above the first 

 interradial is a second, somewhat smaller, pentagonal plate 

 which is about, or a little less than, half within the calyx. 

 This plate, together with the special anal, supports the pos- 

 terior portion of the ventral sac (apparently two columns of 

 plates) , which seems to be composed of rather stout five- to 

 seven-sided plates with no or very small pores at the angles ; 

 they have a botryoidal surface. At one side and on the top of 

 the sac there seems to be a raadreporite plate pierced by large- 

 sized pores. The sac was apparently about the size of the calyx, 



