. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. MESODON. 335 Mesodon Downieana, Bland. Shell umbilicate, umbilicus nearly covered, subglobose, thin, subpellucid, •with obsolete rib-like striae, decussated with crowded microscopic spiral lines, greenish horn-colored ; spire short, obtuse ; whorls 5, convex, the last tumid, anteriorly somewhat gibbous, scarcely descending, constricted; aperture oblique, lunate oval; peristome white, labi- ate, reflected, right margin expanded, columellar margin angu- larly dilated, nearly covering the umbilicus. Greater diameter 10£,
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. MESODON. 335 Mesodon Downieana, Bland. Shell umbilicate, umbilicus nearly covered, subglobose, thin, subpellucid, •with obsolete rib-like striae, decussated with crowded microscopic spiral lines, greenish horn-colored ; spire short, obtuse ; whorls 5, convex, the last tumid, anteriorly somewhat gibbous, scarcely descending, constricted; aperture oblique, lunate oval; peristome white, labi- ate, reflected, right margin expanded, columellar margin angu- larly dilated, nearly covering the umbilicus. Greater diameter 10£, lesser 9| mill.; height, 6 mill. Fig. 217. Helix Doitmieana, , Ann. N. Y. Lye, VII. 420, PI. IV. Figs. 23, 24 (1861). — W. G. BlNNEY, L. & Sh., I. 151 (1869). Mesodon Doivnieana, Tryon, Am. Journ. Conch., III. 47 (1867). M. Doivnieana. Fig. 218. Munroe County; University Place, Franklin County; Tennessee, Whitley County, Kentucky. A species of the Cumberland Subregion. Animal with the usual characters of the genus. Jaw as usual; over 10 ribs. The lingual membrane (PI. VIII. Fig. F) has 35—1—35 teeth, with 12 laterals. The side cusps and cutting points are visible on the second lateral tooth. Mesodon Lawi, Lewis. Shell narrowly umbilicated, globose, surface hardly broken by delicate in- cremental striae, horn-colored; spire elevated, apex obtuse. whorls 4, convex, suture impressed, the last globose, descending, deeply constricted behind the peristome; aperture oblique, lu- nate, narrow, with a linguiform tooth on tJie parietal wall; peri- stome white, thickened, reflected, its terminations approached slightly, that of the columellar somewhat concealing the very narrow umbilicus. Greater diameter 6, lesser 5 mill.; height, 3 mill. M. Lawi. Helix Lawi, Lewis, Proc. Acad. Nat. Sci. Philad., 1874, 118 (Fig.). Probably a species of the Cumberland Subregion. Thus far only found at Hayesvillu, Clay County, North Carolina, in a field, at the roots of Strawberr
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