. Cincinnati quarterly journal of science. Science; Science -- Ohio. 310 3fonograph of the Gasteropoda. Cyrtolites elegans—(S. A. Miller). Shell convolute, the outer volution on the ventral side receiving, in a narrow groove, the sharp dorsal carina of the inner volution and part of the whorl; about two volutions somewhat compressed and rapidly enlarging ; sharply carinated on the dorsal margin; greatest convexity near the umbilical margin; transverse section somewhat cordiform ; aperture deeply notched on the outer margin. Surface marked by numerous, transverse, undulating, subimbricat- ing l
. Cincinnati quarterly journal of science. Science; Science -- Ohio. 310 3fonograph of the Gasteropoda. Cyrtolites elegans—(S. A. Miller). Shell convolute, the outer volution on the ventral side receiving, in a narrow groove, the sharp dorsal carina of the inner volution and part of the whorl; about two volutions somewhat compressed and rapidly enlarging ; sharply carinated on the dorsal margin; greatest convexity near the umbilical margin; transverse section somewhat cordiform ; aperture deeply notched on the outer margin. Surface marked by numerous, transverse, undulating, subimbricat- ing lamellae, or raised lines, having a slight forward direction from the keel of the shell. Diameter of a full-sized spe:'imen, |tli inch ; greatest convexity, jth inch. It is distinguished from Cjrtolites compressus, with which it has sometimes been confounded, by being smaller, fewer whorled, having outer whorl embracing more of the inner whorl, and by having un- dulating lamellae much closer, not so regular, nor undulations so great,. Fig. o\ — CyrtoHtes elegans. Magnified two diameters. and havi ag a stronger forward direction from the keel of the shell. It is distinguished from Cyrtolites Dijeri, which it most resembles, by being destitute of the revolving lines or ridges, and having greater flexure in the forward bearing, transverse lamellae. Figure 2, plate 13, of the Paleontology of Ohio, though a very poor representation of the specimen, I have reason to think belongs to this species. Prof. Meek says of it: " One specimen, in Mr. Dyer's collection, from the Cincinnati rocks, only shows about five of the revolving ridges on each side, and these are very obscure. Its dorsal keel has a marginal line on each side, and shows the raised marks of growth crossing the very narrow space betAveen these to be distinctly curved backward, like those usually seen on the band of Pleurotomaria. In some respects this form resembles C. compressus, Conrad, but it differs materially i
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Keywords: ., bookcentury1800, bookcollecti, bookdecade1870, booksubjectscience
