WAVEELY GROUP SPECIES. 283 



affinities in preparing the text for the press, a part of which I have had 

 to do away from home, and with but few of the necessary facilities at 

 hand. The fact, too, that Prof. Winchell has named and described a 

 number of species of this genus from the same formation, none of which 

 have yet been figured, renders it still more difficult to arrive at satisfac- 

 tory conclusions whether our specimens belong to a new species or not. 



Locality and position : Sciotoville, and various other localities in the Waverly group 

 of the Lower Carboniferous series in Ohio. I think I have also seen the same shell 

 in beds of the same age (Choteau limestone) in Missouri, and the Ivinderhook group 

 of Illinois. 



Productus (undetermined sp.). 



Plate 10, fig. 3. 



This is a larger, wider, and less produced form than the last, with 

 much more distinct longitudinal costse. It much more nearly resembles 

 P. semireticulaius than the last, but has the concentric wrinkles decidedly 

 smaller and less distinct over the visceral region, and doubtless differs 

 in other respects from that species. The costa3 of the species described 

 above are so exceedingly variable that I am not altogether clearly satis- 

 fied that it may not be connected with this by specimens presenting in- 

 termediate characters, though I think it is not. 



Locality and position : Same as last. 



Genus ATHYRIS, McCoy, 18U. 



(Synop. Carb. Foss. Ireland, 128.) 



Athyris lamellosa, Leveille? (sp.). 



Plate 14, figs. 6a, b. 



Spirifer lamellosus, Leveille (1835) ; Mem. Geol. Soc. France, II., 39, figs. 21-23. 

 Spirife7- squamosus, Phillips (1836) ; Geol. Yorks., II., 220, pi. 10, fig. 21. 

 Terebratula lamellosa, DeKoninck (1843) ; An. Foss. Belg., 299, pi. 20, figs. 5a, b, c. 

 Compare Spirigera Hannibal ensis. Swallow (1860) ; Trans. St. Louis Acad. Sci., I., 649: 

 also Athyris crassicardinalis, White (1860) ; Boston Jour. Nat. Hist., VII., 229. 



Shell transversely sub-elliptic, being usually about two-thirds as long 

 as wide, moderately convex; hinge line long, and often nearly or quite 

 straight, but rounding off at the lateral extremities, and never equaling 

 the breadth of the valves ; lateral margins rather narrowly rounded ; 

 front more or less rounded, or forming a transversely semi-elliptic curve 

 in general outline, but usually produced and sub-angular in the middle, 

 at the termination of the mesial fold and sinus. Dorsal valve a little 

 more convex than the other, its greatest convexity being in the central 



