Natural History of New York ...: pt.i-vi

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D. Appleton & Company and Wiley & Putnam, 1879

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Página 67 - Shell subglobose, or obliquely ovoid-conical. Spire moderately elevated ; apex minute. Volutions about four, gradually expanding to the last one, which becomes very regularly ventricose, with the aperture expanded and nearly round, extended on the lower side, with a shallow notch on the anterior margin; upper side of the volutions very...
Página 45 - Surface marked by longitudinal sharp, curving striae, which bend gently backward from the suture, and forward towards the base of the volution, having the greatest curve near the middle, those of the last volution curving abruptly backward to the columellar lip; striae separated by distinctly defined grooves which are a little wider than the ridges; the striae increasing in distance as the shell grows older.
Página 5 - ... angular or marked by an angular carina which often becomes double in old shells, or is rounded on the summit. This angularity or carina indicates, by direction of the striae, the existence of a sinus in the peristome from an early period of growth; and sometimes there may have been two of such sinuosities close together, giving the double carina. There is usually a depression along one or both sides of the carina, with longitudinal folds (obscure plications) on one or both sides, which become...
Página 5 - Shell obliquely subconical or subpyramidal; the nucleus or apex minute and making from one to one and a half volutions which are vertically compressed, and below which the body volution is abruptly expanded; the dorsum angular or marked by an angular carina, which often becomes double in old shells, or is rounded on the summit. This angularity or carina indicates by...
Página 102 - Surface, on the expanded part of the outer volution, marked by fine, close, concentric striae, which are sometimes crowded in fascicles, giving an undulating surface ; the posterior prominent part of the volution is marked on the back, and partially on the sides, by strong, even, arching costae, which are more abruptly and sometimes subangularly curved on the dorsal line. These costae sometimes continue for half the length of the volution anteriorly, gradually becoming obsolete on the middle and...
Página 187 - ... extremity, with a length of seventyfive millimeters. Surface marked by fine closely arranged striae, or frequently with more distant oblique annulations, receding from the aperture or sinuate on the ventral side — the degree of obliquity depending upon the position of the fossil or the relation of the parts exposed to view. Interrupted longitudinal striae are visible in well preserved specimens.
Página 91 - Surface marked by distinct concentric striae, which are sometimes raised in fascicles above the general surface of the shell, and bending gently back from the suture reach the spiral band, crossing which they bend forward more abruptly, making a gentle curve to the suture below. The spiral band at about three-fourths of the width of the volution below the suture is simple, flattened or slightly concave, limited by narrow moderately elevated revolving lines, and marked by the retrally curving striae,...
Página 45 - Shell elongate, subulate. Volutions moderately convex, about thirteen in the largest specimens known, very gradually increasing in size from the minute apex, the last one ventricose. Aperture ovate, narrowing below; columella extended. Surface marked by longitudinal, sharp, curving striae, which bend gently backward from the suture, and forwards toward the base of the volution, having the greatest curve near the middle, those of the last volution curving abruptly backward to the columellar lip. Striae...
Página 69 - Surface marked by two distinct, narrow, revolving carinae on each volution, one just below the suture, and the other near the periphery, with finer intermediate striae which are rarely visible ; the entire surface marked by strong, regular and even concentric striae which rrenulate the revolving carinae, and, passing over the lower one, bend backward to the concave peripheral band ; suture sometimes sharply canaliculate.
Página 27 - Shell subturbinate, sometimes approaching a subglobose form. Spire depressed, or more or less elevated above the outer volution, sometimes nearly on the same plane; volutions three or four, rapidly expanding, the last extremely ventricose, with the lower part projected in the direction of the columella, which is much extended. Aperture subovate, broader above, narrowing and often extended below, "Surface marked by fine subequal concentric striae, crossed by finer revolving striae; the former variously...

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