. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; Zoology. MESODON. 335 Mesodon Downieana, I'land. Shell uiubilicatc, umbilicus nearly covered, subglobose, thin, subpellucid, with obsolete rib-like stria;, 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 obli(j[ue, lunate oval; peristome white, laljl- ate, reflected, right margin expanded, columellar margin angu- larly dilated, nearly covering the umbilicus. Greater di
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; Zoology. MESODON. 335 Mesodon Downieana, I'land. Shell uiubilicatc, umbilicus nearly covered, subglobose, thin, subpellucid, with obsolete rib-like stria;, 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 obli(j[ue, lunate oval; peristome white, laljl- ate, reflected, right margin expanded, columellar margin angu- larly dilated, nearly covering the umbilicus. Greater diameter 10^, lesser 9| mill.; height, 6 mill. Fig. M. Downieana. Fig. 218. Helix Dowiikana, Bland, Ann. N. Y. Lye, VII. 420, PI. IV. Figs. 23, 24 (1861). —W. G. Binney, L. & Sh., I. 151 (1869). Mesodon Downieana, TiiYON, Am. Joum. Conch., III. 47 (1867). 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 La^vi, Lewis. Shell narrowly umbilicated, globose, surface hardly broken by delicate in- cremental stria;, 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 the 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 Hayesville, Clay County, North Carolina, in a field, at the roots of
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