Maryland Geological Survey 257 



This is the most common criiioid of the Oriskany. Usually the arms 

 have been broken off but in the fine collection of Mr. Hartley is a group 

 of two, both of which are nearly perfect, and others preserving fragments 

 of the arms. It was upon collections from Cumberland that Hall based 

 his original description and account of the habits of the genus. 



Occurrence. — Oriskany Formation, Eidgely Member. Cumberland, 

 EInobly Mountain, near Cumberland; east side Nicholas Mountain and 

 elsewhere in Maryland ; Franklin, West Virginia. 



Collections. — Maryland Geological Survey, U. S. jSTational Museum. 



Edriocrinus pocillii'-ormis Hall 

 Plate XL, Figs. 13-15 



Edriocrinus pocilliformis Hall, 1859, Pal. N. Y., vol. ill, p. 121, pi. v, figs. 8-12, 



1861. 

 Edriocrinus pocilliformis Meek and Worthen, 1868, Geol. Survey 111., vol. ill, 



p. 370, pi. vii, figs. 5a, &. 

 Edriocrinus pocilliformis Keyes, 1894, Missouri Geol. Survey, vol. iv, pt. i, 



p. 221, pi. XXX, fig. 7. 

 Edriocrinus pocilliformis Talbot, 1905, Amer. Jour. Sci., 4th ser., vol. xx, 



p. 23, pi. iv, figs. 1-6. 



Description. — " Base hemispheric or subturbinate, often less than a 

 hemisphere, externally smooth or finely granulate : upper margin scolloped 

 with five large and one smaller depression for the insertion of the radial 

 and anal plates. Interior more or less deeply concave, with depressions 

 corresponding to those on the edge of the cup ; the concavity not parallel 

 to the exterior convexity. Eadial plates and arms unknown." Hall, 1859. 



" Infrabasals present but so fused that their number is uncertain. 

 Height from one-half to two-thirds that of the cup as ordinarily found. 

 Basals five, completely fused with each other and with the infrabasals or 

 distinguished from the latter as a narrow protruding band. Suture lines 

 sometimes apparent on the interior. Upper margin scolloped for the at- 

 tachment of the radials and the anal plates. Pleight about half that of the 

 infrabasals. Radials five, often as high as the infrabasals and basals com- 

 bined, and like them, fused to form a part of the cup. In most instances, 

 however, the suture lines between the radials are plainly discernible. As 

 a rule, the union between the radials and basals is not so strong as that of 

 17 



