26 I.ARVIFORM CRIXOIDS 



The surface of the holotype is smooth and entirely unornamented. 



Remarks. — In some respects this species resembles K. pocillus but the 

 proportions are different and its radials are much more convex, thus giving 

 a more pronounced lobation to its horizontal outline. 



Occurrence. — The holotype was obtained from shale directly underlying 

 the Piasa limestone near the center of the NE. )/+ sec. 25, T. 8 N., R. 10 W., 

 Jersey County, Illinois. The other figured specimen was collected by Mr. 

 J. B. Knight from the same stratigraphic horizon in the hollow just north 

 of the right-angle west turn of Scheute Road half a mile southwest of Lack- 

 land Station on the Chicago, Rock Island and Pacific Railway and three 

 quarters of a mile north of Stratman, St. Louis County, Missouri. 



Kallimorphocrinus knighti J. M. Weller, n. sp. 

 Plate I, figs. 7a-b 



Description. — The height of the holotype is 1.48 mm. and the greatest 

 width is approximately the same. Its outline as seen from above is sub- 

 pentagonal. The corners which are formed by the rounded angulations of 

 the radials are more or less narrowly rounded and the sides of the radials 

 meet at a very obtuse angle. The radials make up about three-fourths, the 

 basal disc one-twelfth, and the oral crown one-sixth of the total height. A 

 thin circular stem joint is attached to the base of the calyx. 



The basal disc is subpentagonal with slightly convex sides. It slopes 

 strongly outward and upward from the proximal stem facet which occupies 

 most of its basal surface. The upper edge of the disc is cut by five sharp 

 scallops in which rest the radials. 



The radials are oval below and truncated above. Their height is con- 

 siderably less than twice their greatest width. The median portions of the 

 radials are produced into narrowly rounded longitudinal angulations from 

 which nearly flat sides slope off to the sutures along which the adjacent radials 

 meet at a very obtuse angle. The lateral profile of the radials is convex with 

 the curvature largely localized near the middle so that the greatest width of 

 the calyx occurs at about mid-height. The upper outer edges of the radials 

 are partially beveled and the upper corners are depressed, producing shallow 

 concave notches in which the orals partially extend. 



The articular processes of the radials on the holotype have been partially 

 obliterated but they were apparentlv large and strong. ( )ne of the radials. 

 the anterior one probably, is somewhat larger than any of the others but not 

 large enough to greatly mar the pentamerous symmetry. 



The oral crown, although prominent, does not extend completely to the 

 edge of the radials at their junctions. This portion of the crinoid is rather 

 worn but the details of its structure, such as the shallow depressions of the 



