504 PALEONTOLOGY OF ILLINOIS. 



Length of body, exclusive of the basal pieces, 0.48 inch; 

 breadth, 0.47 iiich; length of dorsal arm to the first bifur- 

 cation, 0.62 inch; entire length, about 1.80 inch; breadth 

 of do. near the middle, 0.10 inch; length of upper dorsal 

 plate, 0.15 inch; breadth of do., 0.20 inch. 



Compared with Prof. HALL'S figure of the body of his C. tunicatus, 

 and with specimens we have identified with that species, this form 

 differs in having the body not narrowing upward, being as wide across 

 just above the constriction as at the base of the dorso-lateral pieces ; 

 the constriction of the sides is also distinctly above, instead of at the 

 middle, while the outer sloping sides of its dorso-lateral pieces are pro- 

 portionally shorter, and directed more obliquely outward. Its dorsal 

 side, instead of being " flattened," is also distinctly concave below the 

 middle. Again, its upper dorsal plate is proportionally smaller, being 

 considerably less, instead of more than half the breadth of the body 

 above the middle, and only just large enough to fill the depression in 

 which it rests without projecting above, while its lower sloping margins 

 are rounded so as to give it a semicircular outline, instead of being 

 straight. 



Compared with C. nodosus, Hall, the only other described species from, 

 this horizon, it will be at once distinguished by the nodose character of 

 the latter. It likewise differs, in the details of its structure, from the 

 various other species described by Prof. HALL from other horizons. 



The specific name is given in honor of Prof. FRANK H. BRADLEY, of 

 Hanover College, late of the Illinois Geological survey, who discovered 

 the typical specimen, and numerous other fossils at the same locality. 



Locality and position Crawfordsville, Indiana j Keokuk division of 

 the Lower Carboniferous series. 



GENUS CATILLOCBimiS, Troost. 

 CATILLOCRINUS BRADLEYI, M. and W. 



PI. 14, Fig. 10. 

 CatiUocrinws Bradleyi, MEKK and WORTHKN. Proceed. Acad. Nat. Sci., Plrila., 1868, p. 342. 



BODY small, basin-shaped, or rather broadly truncated 

 below for connection with the column, and moderately ex- 

 panding upward to the top of the radials supporting the 

 arms. Lower series of plates visible around the top of the 

 column, anchylosed together, and presenting the form of a 



