. Bulletin - United States National Museum. Science. 152 A MANUAL OF AMERICAN LAND SHELLS. cutting- point, is very sbort, reacliing only about half way to the lower edge of the base of attachment. Laterals of same type; the second has a side cutting point. Marginals low, wide, very variable in the denticles, but usually with one long, broad, sharply bifid inner denticle (the inner point much the smaller), and one short, sharp, rarely bifid outer denticle. There are 24 laterals. The twenty-second tooth has the side cutting point; on another membrane, the twentieth (Terr. Moll., V, Plate IX, Fig
. Bulletin - United States National Museum. Science. 152 A MANUAL OF AMERICAN LAND SHELLS. cutting- point, is very sbort, reacliing only about half way to the lower edge of the base of attachment. Laterals of same type; the second has a side cutting point. Marginals low, wide, very variable in the denticles, but usually with one long, broad, sharply bifid inner denticle (the inner point much the smaller), and one short, sharp, rarely bifid outer denticle. There are 24 laterals. The twenty-second tooth has the side cutting point; on another membrane, the twentieth (Terr. Moll., V, Plate IX, Fig. L). GLYPTOSTOITIA.* Animal as in Fatula. Shell widely umbilicated, depressed, with wrinkle-like stricT, solid; whorls G, the last depressed-globose, not falling- at the aperture; aper- ture oblique, subcircular; peristome simple, acute, thickened within, its extremities ai)proached, that of the coluniellar short, scarcely re- flected. Inhabits the Californian Eegion at San Diego. One species only is thus far known, Ncwhcrryannm. Its jaw is low, wide, slightly arcuate, ends but little at- tenuated, blunt; cutting margin without median projection; anterior surface with numerous (about 15), stout, separated Jaw of G. Netchcrryanum. rj^j^^ deeply dcnticulating either margin. Lingual membrane (Terr. Moll., V, Plate X, Fig. A) long and narrow. Teeth 47-1-47, with 17 perfect laterals. Centrals with the base of attachment long and narrow, with greatlj' expanded lower, lateral angles, the upper margin rounded, broadly reflected; reflection large, stout, with obsolete side cusps, but with decided, triangular side cut- ting points; median cusp very stout, short, with a long, acute cutting I)oint reaching beyond the lower edge of the base of attachment. Lat- erals like the centrals, but asymmetrical by the suppression of inner, lower, lateral angle of the base of attachment and inner side cutting point. The transition from laterals to marginals is marked by the lesser proportional develo
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