Cuttings From a Note-Book on Chalk Gasteropods

Abstract

Two years ago, collecting matter for future use, in travelling over the Chalk-lands, I made, in the museums visited, such brief memoranda of striking fossils as might save the trouble of comparison with other specimens. The notes were never intended for publication in their present form, but as any more extended work on the subject is at present impossible, such of them as I have permission to print may be found useful to others engaged on similar work.This series is part of the magnificent collection in the Brighton Museum; to the Committee of which I am indebted for the opportunity of making use of them.Conical, twice as high as wide. Many-whorled; whorls flat and narrow, being fou r times as wide as high. Each whorl is ornamented on the upper and lower sutural margins by a very numerous row of closely-placed tubercles. The anterior row has the tubercles elongated longitudinally; those of the posterior row are more bead-like. Connecting these rows are half as many again narrow, sharp, upright ribs. The tubercles and ribs become not only actually, but relatively much more numerous as the shell enlarges; they are crossed horizontally by a number of (about ten) fine spiral striae.