342 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 



outer margin; the basals very small, occupying only the bottom part. 

 Radials very long, only half their length exposed to view; the attenuate 

 longer half incurving and forming the sides of the concavity ; the exposed 

 part wider than high. First costals quadrangular, their width once and a 

 half their length; the second a little larger and hexangular, their upper 

 angle broadly truncated by the interdistichals. Distichals nearly of equal 

 size, and almost as large as the axillary costal; the upper angle of the 

 second so extremely obtuse as to almost form a straight line; the fixed 

 palmars moderately large and quadrangular. First interbrachial large, 

 generally as wide as long ; the upper part broadly truncated by the two 

 plates of the upper row, which together are as large as the first, and rise to 

 the second arm plate. Interdistichal rather narrow and long. Partition 

 walls narrow, not more than half the width of the arms, except their upper 

 ends which widen conspicuously toward the summit. Summit somewhat 

 flattened ; the central space closed by a short pyramid of small plates. The 

 arms rounded on the back, projecting slightly over the sides of the parti- 

 tions ; the three proximal plates single, and higher than the succeeding ones 

 which deeply interlock. 



Horizon mid Locality, — ISmgam group ; Decatur and Wayne Cos., Tenn. 



Types in the Museum of Comparative Zoology, and in the collection of 

 Wachsmuth and Springer. 



Eemarhs. — This species differs from E. ccelatus, to which Roemer 

 referred it provisionally, by the much more depressed form of the dorsal 

 cup, the proportionally greater length of the arms, the form and size of the 

 various plates, and the mode of ornamentation. 



Eucalyptocrinus crassus Hall. 

 Plate LXXXL Figs, i, 2, 3, ^, ^, 6, IJf, 15, 



1863. Hall; Trans. Albany Inst., Vol. IV., p. 197; also 20tli Rep. N. Y. State Cab. Nat. Hist., p. 323, 

 Plate 11, Eigs. % 3 (second ed., p. 365) ; also, 28tli Rep. (second ed.), p. 141, Plate 17,' 

 Pigs. 1-11, Plate 18, Pigs. 1-9, and Plate 19, Pigs. 2-5. 

 1875. (?) Hall and Whitfield; Geol. Surv. Ohio, Pala^ont., Vol. II., p. 129, Plate 6, Fig. 11. 

 1881. Collet ; llth Ann. Rep. of Geol. and Nat. Hist, of Indiana, p. 272, Plate 17, Pigs. 1-11, Plate 

 18, Pigs. 1-9, and Plate 19, Pigs. 2-5. 

 Syn, Eucali/ptocrinus constridus, Hall ; ibid., p. 273, Plate 15, Pig. 1. 

 Syn. Tjucalyjitocrinus chicagoensis, Winch, and Marcy ; 1865, Mem. Boston Soc. Nat. Hist., p. 90. 



A large species ; the crown sometimes reaching a length of 10 cm. by 

 6 cm. in width ; its length, as a rule, twice the width ; the length of the 



