. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; 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, ^ig. 180. russet horn-color, with stout striae above, smooth be- low; plane above, with 7 (sometimes 8|) or less flat- tened whorls; equally plane below, with 3| full, more convex whorls on a level, then ending in a deep, per- vious umbilicus, the penultimate somewhat overlapped by the last, the antepe
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; 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, ^ig. 180. russet horn-color, with stout striae above, smooth be- low; plane above, with 7 (sometimes 8|) or less flat- tened whorls; equally plane below, with 3| 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- ' g^arTedL ^"' tions joined by an elevated, heavy, tooth-like triangular fold. Greater diameter 15, lesser 13 mill.; height, 4 mill. Polygyra septemvolva, Say, Journ. Acad. Nat. Sci. Phila., I. 278 (1818); Nich. Encycl., 3d ed. (1819) j Binney's ed. 11. —Tryon, Am. Journ. Conch., III. 159 (1867). Helix septemvolva, Binney, Terr. Moll. TJ. S., II. 196 (part), PL XXXVIIT. outer Figs. ; PI. XXIX. Fig. 1.—DeKay, N. Y. Moll., 47 (1843). — Bland, Ann. N. Y. Lye, VII. 131, Fig. on p. 136.—W. G. Binney, 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- ida.^ There are
Size: 1524px × 1639px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorha, bookcentury1800, bookdecade1860, booksubjectzoology
