456 SvsTi'.MATic Palkontology 



This species is rare in the Lower Devonian of Maryland. That it is 

 subject to wide variations is apparent from Hall's figures, and it may 

 be questioned whether that author has figured but one species. However, 

 no further light can be obtained from the few Maryland forms. 



Occurrence. — Helderberg Formation, Keyser Member. Cumber- 

 land, Tonoloway ? Coeymaxs Member. Dawson, Corriganville. New 

 Scotland Member. Dawson, Devil's Backbone. Horizon unknown. 

 Miller's Spring, Cedar Cliff, West Virginia. Oriskany Formation. 

 Locality not known. 



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



[Ohern.] 



Actinopteria communis (Hall) var. 



Description. — A few imperfect specimens from the Oriskany resemble 

 in a general way .1. communis (Hall). The left valve shows fine, alter- 

 nating striae, crossed by finer, concentric strife, giving to the whole a can- 

 cellated effect which is somewhat more marked on the posterior wing. 

 These specimens are very like those figured by J. M. Clarke under this 

 species and may be wholly identical with them. It seems best, however, 

 to designate them as a variety, but their fragmentary condition will not 

 permit definition. 



Occurrence. — Oriskany Formation, Eidgely Member. Winchester 

 Eoad and Millers Spring near Cumberland. 



Collection. — Maryland Geological Survey. 



[Ohern.] 



Actinopteria textilis (Hall) 

 Plate LXXYI, Fig. 5 



Avicula textilis Hall, 1859, Nat. Hist. N. Y., Pal., vol. iii, p. 288, pi. lii, figs. 



9, 10 ?; pi. liii, figs. 2, 3, 5, 7, 10, 1861. 

 Actinopteria textilis Weller, 1903, Pal. N. J., vol. iii, p. 332, pi. xliii, figs. 



13, 14. 



Description. — " Body of the shell obliquely subovate ; length about once 

 and a half the height, becoming regularly convex from the base, gibbous 

 in the middle, and gently depressed along the line of junction with the 



