NO. 2 BRACHIOPOD SUPERFAMILY STENOSCISMATACEA — GRANT 55 



hani from A. simatum n. sp., A. pingue n. sp., and A. cooperorum 

 n. sp. ; it is easily distinguished from the large and globose A. gregeri 

 (Branson). A. rostratum n. sp. has a similarly sharp beak, but is 

 larger and less wedge-shaped than A. kernahani, and has more costae 

 on folds and flanks. A. halli (Fagerstrom) also has few costae, but is 

 larger and less strongly wedge-shaped than A. kernahani. The latter is 

 much less strongly costate than A. pauperum (Belanski) and also dif- 

 fers in its more wedge-shaped profile and more rounded anterior sur- 

 face. 



Occurrence and abundance. — Hungry Hollow Formation, Tile Yard 

 at Thedford, Ontario (45 specimens USNM 26503, 141882-5) ; Hun- 

 gry Hollow Formation, 2.5 miles E. of Arkona, Ontario (16 specimens 

 USNM 141886, 141891) ; Hungry Hollow Formation, 4.1 miles N. of 

 Arkona, Ontario (2 specimens USNM 141887) ; lower part of Center- 

 field Limestone Member of Ludlowville Shale, %. mile E. of milepost 

 357, south side of railroad tracks, 2.5 miles west of East Bethany, N.Y. 

 (7 specimens USNM 141888) ; Centerfield Member, on Shaffer Creek, 

 1 mile north of Centerfield, N.Y. (1 specimen: aff. A. kernahani 

 USNM 141889) ; Prout Formation of Stauffer (1907) ; tributary to 

 Pipe Creek, 1.25 miles E. of Bloomingville, on ridge road, Ohio (1 

 specimen: aff. A. kernahani USNM 99815) ; lower part of Sellers- 

 burg Limestone, Gheens Quarry, on Silver Creek, about 5 miles N. of 

 Jeffersonville, Ind. (1 specimen USNM 141890). 



Age. — Late Middle Devonian. 



ATRIBONIUM PAUPERUM (Belanski) 



Plate 3, fig. 3 



Camarophoria paupera BELANSKI, C. H., 1928, Univ. Iowa Studies in Nat. 

 Hist., vol. 12, No. 7, p. 27, pi. 4, figs. 6-14. 



Shell small for genus, flatly biconvex ; outline transversely subtri- 

 gonal, greatest width slightly anterior to midlength ; commissure 

 strongly plicated ; fold beginning about 2 mm. anterior to brachial 

 beak, normally formed of two strong subsidiary plications, fold high 

 at anterior but not standing high above flanks of valve ; sulcus deep, 

 strongly bounded laterally, with one median subsidiary fold ; lateral 

 folding strong, angular, deeply serrating commissure, numbering two 

 on each flank, each slightly acutely pointed at anterior margin ; ante- 

 rior surface of shell flattened, about perpendicular to dorsal and ventral 

 valve surfaces ; growth lines weak, primarily visible on flattened ante- 

 rior surface. 



Pedicle valve flatly convex, greatest swelling just anterior to beak, 

 slightly recurved just behind margins where plications rise to sharp 

 points ; beak short, sharp, suberect ; beak ridges moderately sharp, 



