This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1895 edition. Excerpt: ... V Genus VOLVULA. Volvulal smithvillensis nov. sp. PI. 3, fig. 8. Specific characterization.--Shell large anteriorly and centrally but attenuated posteriorly; thick; spirally striate near either terminus; columella with one strong fold. This shell has somewhat the form of Actwonella. It differs from V. ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1895 edition. Excerpt: ... V Genus VOLVULA. Volvulal smithvillensis nov. sp. PI. 3, fig. 8. Specific characterization.--Shell large anteriorly and centrally but attenuated posteriorly; thick; spirally striate near either terminus; columella with one strong fold. This shell has somewhat the form of Actwonella. It differs from V. minutissima by its greater thickness, its greatest diameter being located more to the anterior, and by its thick, strong columellar fold. Locality.--Smithville, Bastrop Co., Tex. Geological horizon.--Lower Claiborne Eocene. Type.--Texas State Museum. Genus CYLICHNELLA. Cyliohnella atysopsis nov. sp. PI. 3, fig. 9, a. "Volvula minutissima" Gabb, specimen in coll. Ac. Nat. Sci. Phila. Specific characterization.--General form globose as figured; substance of the shell rather thick; spirally striate; columella with one fold; umbilicated. Locality.--Little Brazos River, near iron bridge, on Mosley's Ferry road. Geological horizon.--Lower Claiborne Eocene. Type.--Texas State Museum. Fig. 9a is the so-labelled V. minutissima of the Academy collection. Genus TEREBRA. Terebra texagyra nov. sp. PI. 3, fig. 10. T. polygyra Heilp., Proc. Ac. Nat. Sci. Phila., 1890, p. 398. Specific characterization.--General form and size as indicated by the figure; whorls about 15; marked as follows: slightly shouldered below the suture; below, two-sevenths of the way to the next suture with a moderately strong spiral stria; ribs about 15 on each whorl, strong above but dying out below, not deflected or dislocated by the subsutural revolving line; columella twisted as shown in the figure. Conrad's T. polygyra has a more slender form, with far less prominent plicte. T. divisurum and T. polygyra both show dislocation at the subsutural line. T. texagyra resembles T. tantula in...
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