Overview

Excerpt from Preliminary Report on the Paleontology of the Black Hills The species described in the following pages were collected in and around the Black Hills during the expedition, and represent the different formations recognized, except the Carboniferous, from which the fossils obtained were few and of little interest. The horizon of the Potsdam formation of the Black Hills appears to be, so far as the fossils will serve to determine, about the same as that of Wisconsin and the neighboring States; and of some of the layers the lithological features are so nearly the same that it would be difficult to distinguish between specimens from the two localities. The purplish-green quartzitic rock from the head of Red Caiion Creek, containing Lingulepis pinniformis Owen sp. and several other Brachiopodous shells, appears to hold nearly the same relation to the rest of the group as does that at the Falls of the St. Croix, from which the species was originally described, namely, near the base; the Red Canon Creek beds resting immediately on the slates of older date (probably Huronian) while the Trilobitic beds and the soft friable layers occur at a horizon of about 100 feet below the Carboniferous. The entire fauna of the Black Hills beds closely resembles that from Wisconsin; although the species are nearly all distinct, the generic facies is the same throughout. Among the fossils from the higher parts of the formation there are quantities of Plant remains belonging to the genus Pal ophycus which, I am informed, cover the surface of the rocks over large areas where exposed, being densely matted together. These beds also hold a position similar to the Plant beds of other localities. The Jurassic formations seem also to be well represented in this region, and many of the beds are highly fossiliferous. The species are not numerous, but the individuals are extremely abundant, many of the slaty calcareous layers being so largely composed of organic remains, mostly Lamellibrauchiates, as to be quite friable and easily broken in the hand, and some of the sandy layers have their surfaces densely covered with the separated shells of one or two species. The absence of Gasteropoda is a noticeable feature at all localities from which specimens have been brought, no example of this class of molluscs being present in the entire collections from this formation. The few species of Freshwater Gasteropoda described, as probably from this horizon, in the Smithsonian Contributions, (Pal. Up. Missouri, ) being still doubtfully referred. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This 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.

Full Product Details

9781332028382

Table of Contents

Reviews

Author Information

Tab Content 6

Customer Reviews

Recent Reviews

Countries Available