256 Systematic Paleontology 



The species is based on one specimen in the collection of Mr. Hartley, 

 but is quite clearly marked as a new species. It is larger than any other 

 American form referred to this genus known to the writer except Horao- 

 crinus polyxo (Hall) from the Waldron Niagara. It has not, however, 

 the interplate ridges of that species and the radially situated plates are 

 not so deeply notched. 



Occurrence. — Oriskany Formation, Eidgely ^Iember. Cumberland. 



Collection. — Frank Hartley. 



Family AGASSIZOCRINIDAE 



Genus EDRIOCRINUS Hall 



Edriocrinus saccdlus Hall 

 Plate XL, Figs. 7-12 



Edriocrinus sacculus Hall, 1859, Pal. N. Y., vol. iii, p. 143, pi. Ixxxvii, figs. 



1-22, 1861. 

 Edriocrinus sacculus Weller, 1903, Geol. Survey N. J., Pal., vol. iii, p. 342, pi. 



xlv, figs. 3-5. 



Description. — " Body more or less obconic or turbinate below and 

 cylindrical above, varying in its proportions of length and breadth. Base 

 varying in form from turbinate to hemispheric, solid, often obliquely 

 truncate or indented below : upper margin marked by six subangularly 

 concave depressions for the insertion of the radial and anal plates. Eadial 

 plates large, longer than wide, inserted into the depressions in the margin 

 of the base, gradually expanding towards the upper margin which is 

 thickened externally, slightly concave for the reception of the plates of the 

 arm. Arms broad at the base, composed of numerous very short trans- 

 versely linear plates, of which ten or twelve or more occur below the first 

 bifurcation : first bifurcation in the middle, and each side again bifurcat- 

 ing on the third or fourth plate above, with each division bifurcating once 

 or twice beyond this; making eight or ten or more divisions at the 

 extremities. Anal plates two, the lower large and of the same form as the 

 radial plates; the second one small and short. Proboscis and summit 

 unknown. Column, none ; affixed to foreign bodies by the solid base." 

 Hall, 1859. 



