LAMELLIBRANCHS. 125 



Pleurophorus oblongus MEEK. 



Pleurophorus pallasi Geinitz, 1866 : Carb. und Dyas in Nebraska, p. 23, tab. 



ii, fig. 4. (In part.) 

 Pleurophorus oblongus Meek, 1872 : U.S. Geol. Sur. Nebraska, p. 212, pi. x, 



figs. 4a-c. 



Shell small, longitudinally oblong, about twice as long as 

 high, moderately convex, particularly along the umbonal slopes 

 from the beaks to the posterior bapal margin, but without any 

 defined angle or ridge there ; cardinal margin nearly straight, 

 and subparallel to the base, about equaling two-thirds the 

 entire length of the valves ; basal margin more or less distinctly 

 sinuous near the middle, at the termination of a broad, oblique 

 impression or concavity, extending from the anterior side of 

 the beaks, under the umbonal slopes, to the lower margin ; 

 anterior margin narrowly rounded below ; posterior side much 

 wider, rounded, or sometimes obliquely subtruncated above ; 

 beaks convex, very oblique, obtuse, located one-seventh to 

 one-eighth the length of the valves behind the anterior extrem- 

 ity ; surface with apparently only fine concentric marks of 

 growth ; muscular impressions faintly marked ; ridge behind 

 the anterior one small ; posterior lateral tooth slender and 

 elongated. 



Horizon and localities. Upper Carboniferous, Upper Coal 

 Measures: Kansas City. 



Astartella vera HALL. 

 Plate xlvi, fig. 6. 



Astartella vera Hall, 1858 : Geology Iowa, vol. I, p. 715, pi. xxix, figs. 3a-c. 

 Astartella vera Keyes,1891: Proc. Acad. Nat. Set., Phila., p. 250. 

 Astartella vera Keyes, 1891: Johns Hopkins Univ. Circulars, vol. Xf, p. 29. 



Shell subquadrate, with beaks somewhat elevated, situated 

 over the anterior margin, which is regularly rounded ; posterior 

 margin truncated. Surface smooth, with concentric wrinkles 

 and fine lines of growth; cardinal teeth stout. 



Horizon and localities. Upper Carboniferous, Lower Coal 

 Measures : Clinton ( Henry county ). 



