. Bulletin - United States National Museum. Science. 470 A MANUAL OF AMERICAN LAND SHELLS. bearing a short, stout cutting point, reaching the lower edge of the base of attachment; side cusps obsolete, but bearing well-developed, short side cutting points. Laterals like centrals, but asymmetrical by the suppression of the inner, lower, lateral angle of the base of attachment and the iuner side cutting point. Transition teeth from the laterals to the marginals with a more developed reflection, a shorter inner cusp, bearing v, greatly developed bifid cutting point. Marginals low, wide, the reflec
. Bulletin - United States National Museum. Science. 470 A MANUAL OF AMERICAN LAND SHELLS. bearing a short, stout cutting point, reaching the lower edge of the base of attachment; side cusps obsolete, but bearing well-developed, short side cutting points. Laterals like centrals, but asymmetrical by the suppression of the inner, lower, lateral angle of the base of attachment and the iuner side cutting point. Transition teeth from the laterals to the marginals with a more developed reflection, a shorter inner cusp, bearing v, greatly developed bifid cutting point. Marginals low, wide, the reflection equaling the base of attachment, and bearing one inner, long, oblique, acutely bifid cutting point, and one shorter, outer, some- times bifid, side cutting point. The only other Pomatia whose dentition has been figured is pomatia^ which shows the same type of teeth (Goldfuss, I. c, Plate IV, Fig. 6), and Sleboldtiana, Pfr. (see Proc. Am. Nat. Soc. Phila., 1875, Plate XXI, Fig. 8), which difi'ers in detail. The jaw of these and of numerous European species is known, and of the same type as in aspersa. Pomatia aspersa, Shell imperforate, subglobose, rather thin, the surface rather coarsely Fig. 514. and irregularly striate and finely wrinkled and indented J the ground-color is yellowish or gray- ish, with chestnut colored bands of various widtli, across which are narrow, undulating flammules of yellowish ; the spire is rather ob- tuse, composed of 4 or 5 moderately convex whorls, the principal one being very large and ventricose; the aperture is large, a little oblique, rouuded-luuate; the peristome white, sharp, turned slightly outward, and in the region of the umbilicus turning over the columella in a broad, appressed callus, which is continued to the upper junction of the peristome. Greatest diameter, 32"'™; height, 22""". Helix aspersa, Muller, Verm., ii, 59.—Pfeiffer, Mon. Hel. Viv., i, 24L—Dk Kay, N. Y., Moll., 47 (1843).
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