Download or read book Second Supplement to the Monograph of the Crag Mollusca with Descriptions of Shells from the Upper Tertiaries of the East of England Vol IV Univalves and Bivalves written by Searles V. Wood and published by . This book was released on 2017-08-29 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Second Supplement to the Monograph of the Crag Mollusca With Descriptions of Shells From the Upper Tertiaries of the East of England Vol 4 written by Searles V. Wood and published by Forgotten Books. This book was released on 2018-02-07 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from Second Supplement to the Monograph of the Crag Mollusca, With Descriptions of Shells From the Upper Tertiaries of the East of England, Vol. 4: Univalves and Bivalves I was thus induced to enter upon a second Supplement, which I at first thought might be confined to a single plate, but when this had been engraved I reflected that as so many species had been introduced into lists of Crag shells, which I had not introduced into my first Supplement from a feeling that the authority for them was too scant or doubtful to justify it, or, in some instances, from a feeling that the identity was erroneous, it was incumbent on me to present to geologists by figured representations the evidence upon which these introductions were based. This, therefore, I have endeavoured to do, and by it have, perhaps, exposed myself to the objection that the plates have been extended to but little purpose, as many of the so-called new species are either very doubtful in themselves, or are merely derivatives from destroyed beds; though most of these beds probably belong either to the Coralline, or to some still older'part of the Crag; to the Oldest Pliocene, now present in Belgium. To such objections my answer would be that I have long felt that the introduction of so many new species into Crag lists, either from the unsatisfactory evidence of a single Specimen, or from the (in my view) improper identification made, or from the presence of mere derivatives, must produce among geologists, especially those abroad, very erroneous conceptions of the Crag Fauna; and that it was to the advantage of science that these evidences should be placed in an appreciable form before the scientific world. I fear that most of the additions thus made of late years to the Crag Fauna, coupled with the antagonism between the views of Dr. Jeffreys, concerning the identification of many Crag shells with recent species (as expressed by the list which accompanies the paper of Prof. Prestwich, in the twenty-seventh Volume of the Journal of Geological Society') and those of myself, will render the subject of the Crag Mollusca, for some time to come, a subject of more perplexity than interest to students of the upper tertiaries. 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.
Download or read book A Monograph of the Crag Mollusca Or Descriptions of Shells from the Middle and Upper Tertiaries of the East of England written by Searles Valentine Wood and published by . This book was released on 1879 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Monograph of the Crag Mollusca written by Searles Valentine Wood and published by . This book was released on 2014 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Monograph of the Crag Mollusca written by Searles Valentine Wood and published by . This book was released on 1872 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Second Supplement to the Monograph of the Crag Mollusca with Descriptions of Shells from the Upper Tertiaries of the East of England written by Searles Valentine Wood and published by . This book was released on 1879 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Univalves and bivalves second supplement written by Searles Valentine Wood and published by . This book was released on 1879 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Second Supplement to the Monograph of the Crag Mollusca with Descriptions of Shells from the Upper Tertiaries of the East of England written by Searles Valentine Wood and published by . This book was released on 1879 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Monograph of the Crag Mollusca written by Searles V. Wood and published by Cambridge University Press. This book was released on 2014-11-20 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published 1848-82, this multi-part monograph describes and illustrates the fossil molluscs of the Pliocene-Pleistocene Crags of East Anglia.
Download or read book A Monograph of the Crag Mollusca Second supplement Univalves and bivalves By S V Wood 1879 Third supplement comprising Testacea from the upper Tertiaries of the east of England Univalves and bivalves by the late S V Wood ed by his son S V Wood 1882 written by Searles Valentine Wood and published by . This book was released on 1848 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Monograph of the Crag Mollusca Or Descriptions of Shells from the Middle and Upper Tertiaries of the East of England written by Searles V. Wood and published by . This book was released on 1848 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Second Supplement to the Monograph of the Crag Mollusca with Descriptions of Shells from the Upper Tertiaries of the East of England written by Searles Valentine Wood and published by Jackson Press. This book was released on 2011-05-01 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many of the earliest books, particularly those dating back to the 1900s and before, are now extremely scarce and increasingly expensive. We are republishing these classic works in affordable, high quality, modern editions, using the original text and artwork.
Download or read book Monograph of the Palaeontographical Society written by and published by . This book was released on 1879 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Supplement to the Monograph of the Crag Mollusca written by Searles Valentine Wood and published by . This book was released on 1872 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Monograph of the Crag Mollusca Or Descriptions of Shells From the Middle and Upper Tertiaries of the East of England Vol 2 written by Searles V. Wood and published by Forgotten Books. This book was released on 2017-12-19 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from A Monograph of the Crag Mollusca, or Descriptions of Shells From the Middle and Upper Tertiaries of the East of England, Vol. 2: Bivalves The muscular fibres by which the edges of the mantle are withdrawn adhere to, and leave a linear impression somewhat within the margin of the shell; and, in some of the Bivalvia, at the posterior side of the animal, are two siphonal tubes, formed by the prolonged portions of the mantle, the lower one is called the inhalent, the upper one the exhalent siphon, these tubes are capable of being protruded by the animal with the assistance of muscles for that purpose, and again withdrawn under the protection of the shell. In animals possessed of these tubes, the withdrawal of them is indicated in an impression on the body of the shell by the retractor muscle, leaving what is called a siphonal scar, or palleal sinus, which generally denotes, by its depth, a cor responding proportion in the length of the tubes; and where the muscular fibres of the mantle adhere to the interior, leaving the impression without an inflection, the animal either has no prolongation of the mantle, or that the tubes are so short as scarcely to be capable of extension beyond the margin of the valves, and the im pression in that case formed by the mantle is parallel, or nearly so, to the outer edge of the shell. These marks, therefore, are of essential service to the Palaeontologist, as they afford the only indications of the form possessed by the animal inhabitant, thus im pressed upon the interior of the valves. It is however to be feared, that a perfectly strict reliance cannot always be placed upon the peculiar magnitude of this siphonal scar, even in specific determination, as a marked deviation from what might otherwise be considered its typical form may occasionally be detected, but it is in those species which are most subject to variation in the outward forms of the shell; as a general rule, this line, when visible, is of the greatest assistance, and at all times a good auxiliary character in the determination of a species. The length of the siphonal tubes, or the consequent indenture or sinuation of the mantle mark in the shell, points out a difference in the animal from those in which the sinus is wanting, or at least nearly so, where it indicates a mantle either without or with very short siphons, giving fair grounds for generic separation; but occasionally, species are met with that are otherwise very closely allied, having - a similar dentition, and bear the same general relationship in regard to the shell, although very unlike in the form of the mantle mark, such as Leda and Nucula, Cardium and Adama, lucina and Lucifzopsis, and cannot, without violence to a natural arrangement, be removed to any distant position. 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.
Download or read book Monograph of the Crag Mollusca written by Searles Valentine Wood and published by . This book was released on 1872 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliotheca Norfolciensis written by Jeremiah James Colman and published by . This book was released on 1896 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt:
