S/fi/is atid A'oo/s of Cr inoiiis. 



ri-:marKvS on the vSTKms and rooTvS of 



CRINOIDS FROM NKAR I.f:BANON, OHIO. 

 Bv Dk. D. T. D. Dvchr. 



Two or three years since, I concluded to find out, if I could, 

 the character of the termination of the column of the crinoid 

 Heterocrinus subcrassus. 



Having a lower silurian slab with about one hundred speci- 

 mens of the calyx, with a great profusion of the columns 

 diverging in every direction, I selected a column attached to 

 its calyx and followed it by uncovering, until I was rewarded 

 by discovering the column diverging into well-defined roots; 

 length of column from calyx 12^ inches, about 1% inches 

 under the surface. 



At this time I believed that the genus Glyptocrinus floated, 

 and was devoid of bases, or roots. About eighteen months 

 ago, something caused me to doubt this, and I commenced 

 the investigation of the termination of the column, and now, 

 after a great deal of work, and after many discouragements, I 

 have been able to so far develop roots on the terminations of 

 the columns of Glyptocrinus neali, G. dyeri, and G. baeri, 

 that I have a specimen of each species, showing the calyx, 

 column, and roots intact on the slab, one slab of G. baeri 

 having on its surface several specimens of that character. 



One character of the specimens surprised me. The diver- 

 sity of the length of the columns between calyx and roots in 

 the specimens just mentioned. The column of G. neali from 

 two to four or five inches, G. baeri from one-half inch to 

 six or eight, G. dyeri from one to four or five inches between 

 calyx and roots. 



I have also found a specimen of Heterocrinus simplex, 

 showing calyx, column, and inverted saucer-like base attached 

 to another column. 



