450 SMITHSONIAN INSTITUTION 



of calyx at base two and a half times its diameter at the radial facets, where 



it ranges from 7 to 10 mm. Parts above radials not known. 



Types.- Kirk's original is in the U. S. National Museum; the other specimens figured 

 are in the author's collection. 



Horizon and locality. Helderbergian, Linden formation, Benton County, Tennessee. 



Edriocrinus sacculus Hall 



Edriocrinus sacculus Hall, Nat. Hist. N. Y. Pal. Ill, 1859, p. 143, pi. 62, figs. 8, 9; pi. 87, figs. 1-22. — 

 Ohern, Geol. Surv. Maryland, Lower Devonian, 1913, p. 256, PI. XL, figs. 10, 11, 12. — Weller, Geol. 

 Surv. N. J. Pal. Ill, 1903, p. 342, PI. XLV, figs. 3-5.— Kirk, Proc. U. S. Nat. Mus. 41, 191 1, p. 112, 

 pi. 11, figs. 14, 15. — Jaekel, Palaeont-Zeitschr. Bd. 1, 1914, p. 383. 



The largest species; represented by the complete crown. Base inverted 

 conical, usually asymmetric with the upper edge oblique, broadly spreading 

 from a narrow rounded apex, enclosing a large cavity of similar form; walls 

 thick, double, with space for fibrous structures between. Radial circlet cylin- 

 drical; RR rectangular, enclosing wide anal plate projecting above them 

 between arm bases. Arms broad and flat, with well defined food-groove; 

 dichotomous, branching two or three times, curving outward and distal ends 

 closely inrolled, forming a rounded cluster exceeding the calyx in diameter. 

 IBr 10 to 12, occasionally more; short, transversely linear, with beveled 

 sutures. Height to width of base in average of 40 large and small specimens, 

 about 1 to 1. Maximum crown from rounded base to top of recurved arms 

 65 mm. high and 40 mm. wide at greatest width of arm cluster; calyx at arm 

 bases, 44 mm. high by 28 mm. wide; base, 27 by 26; maximum free base, 42 mm. 

 high by 35 mm. wide; minimum free base 10 mm. high by 12 mm. wide. Still 

 smaller specimens occur attached to other objects singly or in clusters having 

 about 10 IBr as in this species. 



Jaekel, 1 under the name Lodanella n.ira Kayser, from the Lower Devonian sandstone, 

 Singhofen an der Lahn, figures fragments of a specimen which he compares with Edrio- 

 crinus sacculus; figure 1 is a restoration of the calyx and arms, largely modeled on Hall's 

 figures. The horizon is comparable with the Oriskany sandstone, and the author notes the 

 relationship of a faunal element of the American and Rheinish Devonian. He thinks the 

 affinities of this form are with the Flexibilia. 



Schlueter 2 mentions a species described by Hall in the Palaeontology of New York, 

 Tom. 3, as "Edriocrinus spiralis," — probably intending to cite this species. 



Types. Hall's original in American Museum of Natural History, New York ; those 

 figured by Kirk in the U. S. National Museum. 



Horizon and locality. Oriskany sandstone, Cumberland, Maryland. 



1 Palaeont. Zeitschr. Bd. i, 1914, p. 483, figs. 1-4. 

 1 Zeitschr. Geol. Gesell. XXX, 1878, p. 59. 



