34 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 76 



Plate 2 ^^^^ 



Catillocrinus tennesseeae (Troost) Shumard 26 



Figs. I, 2. Shumard's type, from Button Mould Knob, Kentucky; dorsal 

 and ventral views ; fig. 2 shows the cone of three divided inf ra- 

 basals at the inner floor of the cup. 

 3, 4. Similar views of a maximum specimen from same locality 

 also used by Shumard, having 58 arm openings; the IBB 

 cone is plainly shown at the inner floor of the cup, but its 

 dividing sutures are not visible ; the position of the interbasal 

 sutures connecting with the fused infrabasals, as deduced from 

 other specimens, is indicated as they appeared at various angles 

 and by transmitted light. 



5. Troost's type from White's Creek Springs, Tennessee ; dorsal 



view, showing division of basal ring into three unequal plates by 

 sutures running from the space occupied by the infrabasals, 

 here broken out; the position of two of the sutures is distinct, 

 that of the third obscure, but visible in certain lights. In this 

 specimen the surface is worn smooth by erosion. 



6. A similar, but less eroded specimen with pentagonal IBB area 



vacant and succeeding BB divided by three sutures. 



7. Interior view of part of fractured calyx having most of the 



basals broken away, leaving the infrabasal ring intact, perfectly 

 outlined by the fracture, and plainly divided into three plates. 



xh 



8. Outer (dorsal) view of same; the pustulose surface well pre- 



served, but indistinct in the figure. X f. 



9. Specimen with base ground and polished, showing obscure out- 



line of IBB, and five interbasal sutures; dorsal view. 

 ID. Ventral view of weathered specimen, showing the openings of 



dorsal canals at the arm facets, and their relation to the food 



grooves ; also the extent, form and proportions of the raised 



process, 

 loa. Ventral view of smaller specimen with the infrabasal cone well 



defined. 



11. Similar view of another large specimen, showing further details; 



the dorsal canals are seen passing inward under the floor of the 

 food grooves. Division of basals into more than three plates is 

 indicated in this and figure 10, not with complete regularity, 

 but exactlj»as the inner floor of the calyx appeared to the artist 

 without suggestion. 



12. Section of radial transverse to the dorsal canals, showing their 



entrance below the level of the food grooves. X 2. 



13. Vertical section of dorsal cup, to show the great thickening at 



upper margin of radials contrasted with the extreme thinness 

 of the base. X |. 



