LARVIFORM CRINOIDS 25 



however being slightly wider than the others. This oral is also distinguished 

 by a tiny pore near its center. Above the radials and along the sutures be- 

 tween the orals in one specimen are five small openings which were probably 

 continuous with the ambulacral grooves of the arms. 



The surface of the plates was apparently originally smooth although the 

 specimens, which are silicified, are slightly roughened. The preservation of 

 the plates suggests a minutely porous surface. 



Remarks. — This species is typical of the simpler type of Kallimorpho- 

 c ri)i its which has a lobed horizontal outline and whose radials have not de- 

 veloped longitudinal angulations. It is unnecessary to compare it with any 

 of the foregoing species. 



Occurrence. — This species occurs in a dark limestone not far above the 

 base of the Pennsylvanian section near the center of the N. ^ sec. 35, 

 T. 21 N., R. 9 W., Warren County, Indiana. 



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

 Plate II, figs. 2a-3b 



Description. — The calyx is small and the width considerably exceeds the 

 height which in the holotype is 1.30 mm. The outline of the cup as seen 

 from above or below is strongly five-lobed owing to the very convex radials, 

 whose margins meet at an angle along the suture. The radials form about 

 four-fifths, and the basal disc about one-twelfth of the height, and the oral 

 crown is twice as high as the basal disc. 



The basal disc is low and pentagonal in outline as viewed from beneath. 

 Its upper edge is cut by five deep scallops for the reception of the radials. 

 The circular stem facet does not occupy the entire under surface of the disc ; 

 its surface is shallowly concave surrounded by a raised border. 



The radials are suboval in outline, about one and a half times as high 

 as wide. Their outer surfaces are strongly convex both longitudinally and 

 laterally. The longitudinal convexity is most pronounced in the lower half of 

 the radials, resulting in the greatest width of the calyx being developed at a 

 position about one-third of the distance above the base. The upper outer 

 edges of the radials are beveled and their distal surfaces are occupied by 

 articular processes for the attachment of the arms. The upper corners of 

 the radials are beveled so that the arm facets are separated by small and 

 shallow concave notches in which the orals rest. 



The articular processes are not well preserved but they appear to be 

 similar to those of the other species here described. 



The calyx is surmounted by a five-lobed oral crown which does not 

 overhang the radials. The upper surface of each oral is broadly and shallowly 

 concave. 



