ACTINOCEINID^. 575 



arms from the axillary. Arms six to the ray, rounded on the back * and 

 slightly tapering, biserial from the third plate up. Pinnules extremely long, 

 and to nearly their full length provided with small hooks, which slightly 

 overlap the adjoining pinnule above. Regular interbrachials : 1, 2, 2 ; the 

 anal plate followed by 2, 3, and 3 plates. Structure of the ventral disk un- 

 known. Anal tube long, slender in the upper part, and composed of small 

 convex pieces. Column of more than average size ; the nodal joints pro- 

 jecting, and rounded at their outer margins. 



Horizon and Locality. — Waverly group ; Richfield, Ohio. 



Ti/pes in the New York State Cabinet at Albany, N. Y. 



Remarks. — This and the two preceding species form a little group by 

 themselves, approaching in some of their characters Cactocrinus ; but they 

 must be referred to Actinocnmis, as the arms of the different rays are 

 arranged in groups, which are separated by a number of interbrachial 

 plates, and the bifurcations above the distichals take place from the sec- 

 ond plate of each order, and not from the first as in that genus. 



Actinoerimis asperrimus (M. and W.). 

 Plate LX. Figs. 5 and 6. 



1869. Strotocrimis Q) asperrimus — Meek and Woethen ; Proceed. Acad. Nat. Sci. Pbila , p. 160. Also 



Geol. Rep. Illiuois, Vol. V., p. 3i9, Plate 8, Fig. 3. 

 1S81. Aciiiiocri)ius asperrimus — W. and Sp. ; Kevisiou Palceocr., Part II., p. 142. 



Calyx of medium size, urn-shaped, its width at the arm bases equal to its 

 length. Dorsal cup obconical to the top of the costals ; the distichals and 

 the succeeding fixed brachials spreading horizontally, but without forming a 

 continuous rim, there being deep interradial grooves, and smaller ones be- 

 tween the main branches of the rays. Plates almost flat to strongly convex, 

 their ornamentation somewhat variable, Figs. 5 and 6 representing the ex- 

 tremes, and the type figured by Meek and Worthen an intermediate form. 

 In all these specimens, however, there are ridges radiating from the centres 

 of the plates to adjoining ones, three generally between the radials and 

 basals, and one between the other plates. 



Basals three times as wide as high, deeply grooved along the sutures, 

 and distinctly lobed from a dorsal aspect; the lower edges scalloped and 



* A flattening of tlie arms, as described by Hall, does not exist in any of our specimens. 



