INVERTEBRATE FOSSILS OF THE COAL MEASURES. 



RADIATA. 



CRINOIDEA. 



Genus CYATHOCRINUS, Miller, 1821. . (See page 175.) 



Cyathocrinus? sangamonensis, M. and "W. 



PI. 26, fig. la, lb. 



Cyathocrinus ? sangamonensis, Meek and Worthen, June, 1861. Proceed. Acad. Nat. 

 Sci., Pbilad., p. 392. 



Body large, semiovate beneath the summit of the first radials, 

 composed of rather thin plates, which are smooth, somewhat 

 convex, and connected by strongly defined, subpunctate sutures. 

 Base moderately prominent, rounded below, pentagonal in out- 

 line, and equaling about half the breadth of the body, formed 

 of equal, regularly pentagonal pieces, which are a little wider 

 than long; columnar facet round, deep and about one- third as 

 wide as the base. Subradial pieces large, as wide as long, three 

 of them hexagonal, and two heptagonal, with unequal sides. 

 First radials wider and shorter than the subradial plates, about 

 twice as wide as high, pentagonal, and of nearly equal size 

 and form; the superior side of each horizontally truncated, 

 and considerably longer than either of the basal margins, 

 which are longer than the vertical, lateral edges. First anal 



