12 A Contribution to the Lower Devonian Faunas of Maryland 



Edriocrinus pocilliformis 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 Wortlien, 1868, Geol. Survey 111., vol. iii, 



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., 4tli ser., vol. xx, 



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



Description. — " Base hemisplieric 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. 



" Infra basals 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. Height 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 

 basals with infrabasals ; and the cup is generally broken oil at the top of the 

 basals. Since in no specimens are brachials preserved, the union of 

 brachials with radials must have been still weaker. Anal plates as high as 

 the radials, but only half as wide. Radials and anal gently convex, sloping 

 in all directions from the center of the plate. Arms and ventral disc un- 

 known. The attachment scar is visible on a ninnber of specimens, and in 

 some is a short distance up on the side of tlie enp. rather than on tlie 

 bottom." Talbot, 1905. 



