Figures and Descriptions on Canadian Organic Remains

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Excerpt from Figures and Descriptions on Canadian Organic Remains: Decade IThe genus is by no means rare in the old deposits of the Silurian seas, and apparently there were several very distinct species, some of which are yet unpublished, and one, M. Pcachii (salter), which hue the operculum extravagantly elongated and curved, occurs in plenty in a rock very like the Canadian limestone, and full of similar types, in the north-west angle of Scotland. It has been figured, and its locality described, by Sir R. I. Murchison, in the Quarterly Journal Geological Society for 1858. Another is plentiful in the Llandeilo limestones of the south of Scotland.Dmtim.-.m Lugosi, when perfect, is fully three and a half inches wide, and is conspicuous for the great ¿atness of its lower or whorled side, and the fewness of its whorls, for, if we except one or two minute inner once, there are but two or three distinct whorls, which diminish so rapidly in breadth that the outer is at least thrice the width of the preceding ones in succession, and greater than that of all the inner whorls taken collectively: in M. Magma it is greatly less than these. The whorls are very gently convex between the sutures, which are sharply marked though not deep, and are closely striated by regular sharp-arched lines of growth. The sides of the whorl are steep, pyramidal, the depth exceeding the width of the whorl, and are furrowed by a number of deep grooves, sometimes 16 or 17, a few of which are interlined with smaller ones. Occa sionally seven or eight only are present, or a deep one (figure 3) occurs at a short interval but this may be the result of injury.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.