FROM THE PALAEOZOIC ROCKS OF INDIANA, KENTUCKY AND OHIO. 



465 



Columnar opening in all parts of the column is of the same form in all its sections, when 

 broken, as that penetrating the body through the basal pieces. 



The surface of the calyx, below the free rays, irregularly granulose. 



Size of Specimen. 



Greatest diameter, ......... 



Vertical height to free rays on the largest piece, 



Vertical height to the free arms on longest ray, 



Diameter of columnar facet, ....... 



Greatest diameter of basal pieces united, 



This species will be readily distinguished from all known crinoidea. 



INCHES. 



1.36 

 .44 



.77 

 .30 

 .78 



Genus Zeacrinus* Troost. 



Synon. Cupressocrinus (sp.), McCoy, 1849. Ann. Mag. Nat. Hist., 2d Ser., Vol. II, p. 224. Not 

 Gold., 1882. 

 Poterioorinus (sp.), do Koninck and Lehon, 1854. Bechorch. Crinoidcs, p. 91, and of some others. 

 Hydreioorinus (sp.), do Koninck, 1858. Bull. Acad. Boyalo Belgkpie, 2d Ser., t. iii, p. 19. 

 Zeaciunus (Troost), Hall, 1858. Iowa Report, Vol. I, Part 2d, p. 541. 



Zeacrinus Stimpsoni, n. s. 



Bl. XXVII, Bigs, m, m 1. 



Body sub-cylindrical; slightly constricted at the summit of the subradial plates; com- 

 posed of plates covered closely with fine granules ; centre of subradial plates gibbous ; 

 base small ; hidden by the column ; depression at the base- broad, extending to the centre 

 of the subradials, which arc nearly of equal size, that under the anal field being the largest; 

 it is six-sided; the five other pieces of the subradials are five-sided; about three times as 

 Ion"- as wide; sharply curved at the margin of the basal pit. First radials nearly as long 

 as wide ; squarely truncated for the reception of the second radials ; angular below ; deeply 

 interlocked between the subradials ; the lower part prominent as high as the upper extrem- 

 ity of the subradials ; deeply depressed midway between the summits of the subradials and 

 the base of the second radials ; at their junction with the second radials enlarged, forming 

 a lip or ridge along the suture between them and the second radial pieces. Second 

 radials, five; lanceolate ; about as wide as high; five-sided; vertical sides very short, full 



or ridged along the centre of the pieces ; margins prominent ; deeply depressed toward the 



* 

 * Tho synonymy of the genus above is extracted from Beports of Geological Survey of Illinois, 

 Vol. II, p. 185. 



vol. xiii. — 59 



