Description of Four JSFgw Species, etc, 233 



Collected at Cicero and Bridgeport, near Chicago, Illinois, in 

 magnesian limestone of the age of the Niagara Group, b}^ W. C. Egan, 

 Esq., of Chicago. 



Glyptocrinds shafferi, var. germanus, n. var. 



riate VII., fig. 2, view of a specimen, natural size, showing the bifurcation of the arms on 

 the twelfth plate; fig. 2a, the same magnified. 



This beautiful little variet}- is more slender and elongated than the 

 t3'pe of G^. shafferi, and the free arms bifurcate on the twelfth plate in- 

 stead of the ninth plate as in that species. The body is also more 

 robust in the species than in the variety. 



The plates in this variety are smooth and without any evidence of 

 ever having been sculptured. The basal plates are minute, being only 

 visible with the aid of a magnifier. The first vadials are heptagonal, 

 and larger than the succeeding radials. The second radials are small 

 and hexagonal. The third radials are pentagonal, and support on the 

 upper sloping sides the free arms. The first interradials are hexag- 

 onal. These are succeeded by two small interradials, and upon the 

 azygous side there are several more. The arm plates bear strong- 

 pinnules. 



The specimens illustrated are in my collection, and were found in the 

 Hudson River Group, at Cincinnati, at an elevation of less than 400 

 feet above low-water mark in the Ohio river. 



Glyptocrinus shafferi (S. a. Miller). 



Plate VII., fig. 3, specimen natural size ; fig. 3a, the same raagnifieil; fig. 3&, the column of 

 this species wound around another crinoid column and terminating in a point; fig. 

 8c, the same magnified. 



This species was described in the Cincinnati Quarterl^^ Journal of 

 Science, Vol. 2, p. 277 (1875), but the wood-cut illustration was in- 

 »correct. The species is readily distinguished b}' its small size, short 

 calyx, coarse pinnules, and banded column. I have not reproduced 

 the t3'pe specimen but have chosen another because it shows part of 

 the column. 



The column tapers to a point at the lower eml, and therefore the 

 species did not attach by a flattened base as Heterocrinus simplex, and 

 II. heterodactijlus attached, nor b}" roots as Anomalocrinus incurvus 

 did. It was a free crinoid that attached itself to other objects at will, 

 b}^ means of an extremely flexible column. The specimen illustrated 

 shows this character. We have the tapering end of this species wound 

 around a crinoid column of a distinct species, almost as neat as a 

 thread can be wound upon a spool. The column gradually tapers as 

 it coils, until it becomes so small as to be scp^rcely visible to the naked 



