298 PALAEONTOLOGY OF OHIO. 



sinus under the posterior ear, as well as in some of its less important 

 details. 



Locality and position : The specimens figured on our plate are from the Waverly 

 group of the Lower Carboniferous, at Newark, Ohio. Through the pohteness of Prof. 

 A. Winchell, I was permitted to make tracings for comparison from drawings he has 

 prepared of this shell from the same horizon in Michigan. 



Genus PAL^ONEILO, Hall, 1870 ? 

 (Prelim. Notice Lamellib. Upper Held., etc., 6.*) 



Paljeoneilo Bedfoedensis, Meek. 



Plate 15, flgs. 3a, 6, c. 



Shell subovate, compressed, or moderately convex, height more than 

 three-fourths the length, the highest point being in front of the middle ; 

 basal margin semiovate, most prominent antero-centrally, from near 

 which it ascends with a slightly straightened, oblique outline behind, 

 and rounds up oblique to the front; posterior margin narrowly rounded, 

 and somewhat compressed; anterior side shorter and more broadly 

 rounded; dorsal margin arcuate, declining more abruptly in front of the 

 beaks, which are moderately prominent, and situated a little more than 

 one-third the length of the valves from the anterior margin. Surface 

 ornamented by very fine, regular, cl^pely arranged concentric striae, that 

 become obsolete on the posterior third of the valves. Oblique posterior 

 sulcus very faintly indicated, or entirely wanting. 



Length, 0.57 inch; height, 0.42 inch; convexity, about 0.14 inch. 



This species seems to be most nearly allied to P. brevis, from the New 

 York Chemung, but differs in not being " very ventricose," and in having 

 its lines of growth very regular, instead of " irregular." Like that 

 species, its oblique posterior sulcus or constriction is quite nearly obso- 

 lete. I have not seen its hinge clearly enough to be entirely sure that it 

 belongs to the group Paleeoneilo; but from its crenate hinge margin, and 

 general form, it probably belongs to that genus. 



Locality and position : Bedford, Ohio. Bedford shale of the Waverly group. 



* I cite this paper here and elsewhere, with the above date, not because I hnow it 

 to have "been properly published at the time, but because I have heard of a few copies 

 being sent out during the year 1870, one of which I have seen. Neither this copy, 

 nor, so far as I can learn, any of the others, had any title page or author's name at- 

 tached ; but it has been attributed to Prof. Hall in a notice published in the Ameri- 

 can Journal of Science and Arts. 



