687 



Plat. 



Platycrinus contritus, Hall. Crinoids of the Waverly 

 sandstone of Ohio, 1863, Pal. Ohio, Vol. 2, 1875, 

 page 166, plate 11, fig. 4, a specimen showing 

 the peculiar form of the basal plates; the 

 arms, preserved for half their length showing 

 the mode of bifurcation; column unknown; 

 ^y belongs to type of P. hurlingtonensis and its 

 varieties. Waverly shales of Summit Co., O. 

 /}^f — Pocono formation^ X, » 



Platycrinus corrugatus. Owen and Shumard, 1852, pi. 



5A. f. 2, a, 

 b, c, (d), e, 

 showing 

 corrugated 

 surface o f 

 sc apul ar 

 plate ; Bur- 

 ling, lime, 

 Iowa. — XL 



Platycrinus discoideus. Owen & Shumard, Geol. of 



Wis. etc., plate 5A, fig. 1, a, b, show- 

 ing the form of the surface to which 

 c^^i the arms of this stone lily was jointed 

 into the cup or head. Burlington 

 limestone^ Iowa. — XL 



Platycrinus graphicus, Hall 17th Rt. Crinoids of the 



Waverly sand 

 ston e, O h i o, 

 1863.— Pal. 

 Ohio Vol. 2, 

 > 1875, page 166, 

 plate 11, fig. 2; 

 b ody plate 



broken and crushed ; showing mode of forking of the arms 5 

 surface of plates obscurely marked by radiating lines of nodes ; 

 column of alternate thick and thin joints; differs from P, con- 

 tritus in having longer and slenderer arms, and only 4 from each 



TaJ.Ohw 







