. Bulletin - United States National Museum. Science. 390 A MANUAL OF AMERICAN LAND SHELLS. througbout, ending in a stout, oval bulb, into which the vas deferens enters. The retractor muscle is inserted above the entrance of the vas deferens. Mesodoti divestiis, Gould. Shell imperforate, depressed, somewhat discoidal, of medium thick- ness and a dingy horucolor, sculptured with coarse, oblique furrows; Fig. 424. spire slightly convex; whorls about 6, a little convex, and separated b}^ a well-imin'essed suture; the outer whorl is a little augular at its periphery; beneath it is more smooth, mode
. Bulletin - United States National Museum. Science. 390 A MANUAL OF AMERICAN LAND SHELLS. througbout, ending in a stout, oval bulb, into which the vas deferens enters. The retractor muscle is inserted above the entrance of the vas deferens. Mesodoti divestiis, Gould. Shell imperforate, depressed, somewhat discoidal, of medium thick- ness and a dingy horucolor, sculptured with coarse, oblique furrows; Fig. 424. spire slightly convex; whorls about 6, a little convex, and separated b}^ a well-imin'essed suture; the outer whorl is a little augular at its periphery; beneath it is more smooth, moderately convex, with the central region exca- h vated and covered with a glazing of white callus; the aperture is lunate and very oblique; the peristome is white, broadly reflected, its basal portion horizontal and its outer portion flexuous. Greater diameter 20, lesser 15""»; height, Oram Eeiix dcjeda, GouLD, Terr. Moll., ii, dl. Not preocc. in Mesodon. Helix abjecla, Gould, Proc. Bo-st. Soc. Nat Hist., iii, 40 (Oct., 1848); Terr. Moll., ii, 122, pi. xii, a, fig. 2.—Pfeiffer. Mon. Hel. Viv., iii, 270. Helix divesia, Gould, Terr. Moll., ii, 357.—W. G. Binxey, Terr. Moll., iv, 51; L. & Sh., i, 13f (18(i9).—Pfeiffer. Mon. Hel. Viv., iv, 322. Mesodon divesia, Tryon, Am. Journ. Concb., iii, 45 (1867).—W. G. BIXXEY, Terr. Moll., V, 329. Washita Springs, Arkansas; Vernon County, Mississippi. It may prove to be a species of the Texan Subregion. Jaw with 10 ribs. Lingual membrane (Terr. Moll., Y, Plate XYI, Fig. V) as in albo- lahris ; teeth 4G-1-4G, with IG laterals. The genitalia are as usual in the genus; the penis sac is very long, cylindrical, stout, tapering at the top; the vas deferens enters at its apex; the retractor muscle is attached to the vas deferens; the genital bladder is short, oval, stout, on a short, stout duct. Mesodon jejiiiiiis, Say. Shell umbilicated, subglobose; epidermis corneous, nearly smooth; Fig. 425. spire rather prominent; sut
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