The small size, great angle of divergence at the beak and sharp-pointed beaks easily distinguish this species from other members of the genus from the Coal Measures. =Pleurophorus whitei=, n. sp. Plate V, figs. 5, 5_b_. Pleurophorus —? White, Bull. U. S. Geol. Surv. 77, p. 27, pl. iv, figs. 5–10. Shell of medium to large size, transversely ovate, with the depth of the shell greater at the anterior than at the posterior end. Beaks moderately prominent, subterminal; umbonal ridge prominent, extending obliquely to postero-ventral margin. Hinge straight or arcuate, usually about three-fourths the length of the specimen. The right posterior lamina is well shown on good casts. The anterior adductor impression is usually prominent, being set apart by the depression produced by the ridge behind it. The impression of the two cardinal teeth is also visible. The anterior margin drops obliquely downward from the beak nearly to the middle of the shell, when it rounds, rapidly at first, into the ventral margin, which may be straight, somewhat sinuous or even convex on approaching the postero-ventral region: at the end of the umbonal ridge it rounds rapidly into the posterior, oblique truncation, reaching the hinge at an oblique angle. The lines formed by the hinge and ventral margins converge toward the posterior, thus leaving the greatest depth of the shell in front. Above the umbonal ridge the shell is obliquely flattened to the hinge. The surface, as shown in excellent molds, is ornamented only by fine lines of growth, which are sometimes a little stronger beneath the beak than elsewhere, and weaken on and above the umbonal slope. Position and locality: This species is found in the Upper Coal Measures, upper Wabaunsee stage, east of Barrett, Kan. This is the only locality known to the writer where this shell, abundant in the Permian, is found below the Wreford limestone. Types from Permian west of Stockdale, Kan., “about 100 feet above Cottonwood limestone.” Collected by Prof. E. A. Popenoe. This species is extremely variable, as shown in Professor White’s figures, above cited. The short shell with the posterior shallower than the anterior end is in sharp contrast to most of the species of the genus. In surface ornamentation it resembles _P. tropidophorus_ more closely than any other species. It is distinguished from _P. subcuneatus_ Meek by its short, thick form and larger size. This species is the more abundant of the two in the Permian rocks of the Big Blue series, while _P. subcuneata_ only has been identified from the Cimarron series. =Allorisma kansasensis=, n. sp. Plate V, figs. 6, 6_d_.