LYMN^EID^E OF NORTH AMERICA. 99 



L. & F. W. Sh. N. A., II, p. 72, 1865.— Meek, U. S. Geol. Surv. Terr., IX, p. 

 598, pi. 45, fig. 5, 1876.— White, Bull. U. S. Geol. & Geog. Surv., Terr., Ill, p. 

 613, 1877; 3rd An. Rep. U. S. Geol. Surv., p. 446, pi. 32, figs. 26-27, 1882. 



Lymncea meekii Cockerell, Nautilus, XXII, p. 70, 1908. 



"Shell rather large, conical-subovate ; spire less than half the 

 length of the shell, acutely pointed at the apex ; volutions five and a 

 half to six, convex, last one ventricose, and comparatively large ; suture 

 well defined. Aperture rather narrow-ovate, angular above and 

 rounded below ; lip slightly dilated at the lower part of the columella ; 

 surface marked by moderately distinct lines of growth. 



"Length, 1.15 inches; breadth, 0.66 inch; apical angle nearly reg- 

 ular, divergence 54°." (Meek.) 



Type : Location not ascertained. 



Horizon : White River formation, Oligocene Period. 



Locality : Pinot's Creek, South Dakota. 



Remarks : "This fine Limncea is quite similar to several of the 

 species figured by Edwards in his Monograph of the Eocene Mollusca 

 of England, published by the Palseontographical Society, but seems to 

 present well-defined specific differences from them all." (Meek.) 



Meekiana is strongly suggestive of some specimens of the recent 

 Galba catascopium Say. It is one of the largest of the fossil Lymnseas 

 (excepting Steam's maxima) as well as one of the most characteristic. 

 For some reason not apparent to the writer, Dr. White used the specific 

 name meekii in his report on the non-marine Mollusca, instead of the 

 original name meekiana. There seems to be no warrant for changing 

 the name, other than that of classical purity, which, as remarked before, 

 cannot be taken into account in systematic nomenclature, where sta- 

 bility is of the first importance. 



Galba shumardi (Meek). Plate XVI, figures 26, 27. 



Limncea shumardi Meek, U. S. Geol. Surv. Terr., IX, p. 599, pi. 45, fig. 6, 

 1876.— White, Bull. U. S. Geol. & Geog. Surv. Terr., Ill, p. 613, 1877.— Miller, 

 Journ. Cin. Soc. Nat. H., IV, p. Ill, 1881; Mes. & Caenoz. Geol., p. 253, 1881.— 

 White, 3rd An. Rep. U. S. Geol. Surv., p. 446, pi. 32, figs. 28-29, 1883 — 

 Marcou, Proc. U. S. Nat. Mus., VIII, p. 340, 1885. — Schuchert, Bull. U. S. 

 Mus., 53, i, p. 356, 1905. 



Lymncea shumardi Cockerell, Nautilus, XXII, p. 70, 1908. 



"Shell rhombic-subovate ; spire less than half the entire length, 

 very acute at the apex ; volutions five and a half, convex, last one not 

 ventricose, rather oblique ; suture moderately well defined ; surface 

 marked by distinct lines of growth, and sometimes having, on the upper 

 part of the body-whorl, a few broad, obscure, vertical or oblique folds ; 

 aperture ovate, rounded below, and angular above. 



