. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. POLYGYRA. 281 In the region of the Rio Grande, both in Texas and Tamaulipas. A species of the Texan Subregion. Animal not observed. Polygyra septemvolva, Say. Shell broadly umbilicated, subcarinated, discoidal, Fig. i8o. russet horn-color, with stout striae above, smooth be- low; plane above, with 7 (sometimes 8h) or less flat- tened whorls; equally plane below, with 3J- full, more convex whorls on a level, then ending in a deep, per- vious umbilicus, the penultimate somewhat overlapped by the last, the antepenultimat
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. POLYGYRA. 281 In the region of the Rio Grande, both in Texas and Tamaulipas. A species of the Texan Subregion. Animal not observed. Polygyra septemvolva, Say. Shell broadly umbilicated, subcarinated, discoidal, Fig. i8o. russet horn-color, with stout striae above, smooth be- low; plane above, with 7 (sometimes 8h) or less flat- tened whorls; equally plane below, with 3J- full, more convex whorls on a level, then ending in a deep, per- vious umbilicus, the penultimate somewhat overlapped by the last, the antepenultimate much the largest; aperture very oblique, remote from the axis, subreni- form, constricted behind the peristome; peristome thickened, bluntly reflected, continuous, its termina- enlarged. tions joined by an elevated, heavy, tooth-like triangular fold. Greater diameter 15, lesser 13 mill.; height, 4 mill. Polygyra septemvolva, Say, Joura. Acad. Nat. Sci. Phila., I. 278 (1818) ; Nich. Encycl., 3d ed. (1819); Binney's ed. 11.—Tryon, Am. Joum. Conch., III. 159 (1867). Helix septemvolva, BiNNEY, Terr. Moll. II. S., II. 196 (part), PI. XXXVIII. outer Figs. ; P*l. XXIX. Fig. 1. —DeKay, N. Y. Moll., 47 (1843). — Bland, Ann. N. Y. Lye, VII. 131, Fig. on p. 136. — W. G. Binxey, Terr. Moll., IV. 89, part; L. & Sh., I. 104 (1869). — Pfeiffer, V. 419 (1868). ? Helix volvoxis, Pfeiffer, see below. St. Augustine, Florida. Confined to the Florida Subregion. Animal (see p. 262) brownish, eye-peduncles darker, very long and slender, eyes black; foot narrow, thin, semi-transparent, receiving its color, in some de- gree, from the substance on which it is placed, not projecting behind the shell when in motion; length less than twice the breadth of the shell, which it car- ries nearly horizontal. The shell described and figured above, which is, no doubt, the form called septemvolva by Say, is only found, to my knowledge, at St. Augustine, Flor- There are, however, associa
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