Phylogeny of the Echini, Vol. 7

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Excerpt from Phylogeny of the Echini, Vol. 7: With a Revision of Palaeozoic Species, With Seventy-Six PlatesDuring a year recently Spent in Europe, Opportunity Offered to study most of the European species Of Palaeozoic Echini and in many cases the types. In this country Similar Opportuni ties have been enjoyed with American species. The great liberality and kindness of all to whom I applied for permission to study material is later acknowledged in detail, but I cannot refrain from saying here that the freedom and liberality with which the choicest and rarest material was placed in my hands and every facility offered for study at home and abroad, was one of the pleasantest experiences of my life.The present memoir is naturally divided into three parts: first, a study Of the development and comparative morphology of Echini, based on the young, adult, fossil, and living types, second, a proposed systematic classification of Echini based on the preceding studies, third, a revision of Palaeozoic Echini comprising the systematic description of all known forms.The late Professor Alpheus Hyatt originated most important and novel methods of study in Palaeontology. It is both an Obligation and a privilege to say that during many years, when closely associated with him as student and assistant, he impressed upon me the important principles of stages in development, senescence, acceleration, and parallelism. During my first sea-urchin studies I had the privilege Of his ever ready sympathy and personal help. I have tried to carry out this work on his lines and as he would have done it, so far as in me lay. The Hyatt principles are the pith and center Of the work, and I take pleasure in feeling that his views worked out largely on the Mollusca are supported and strengthened by their applica tion to another group of animals.In revising a group, it is most important to see the types or original specimens on which species have been based. Omitting Incertae Sedis, the types have been studied of 69 Of the 119 species Of Palaeozoic Echini described in this memoir. Specimens of 96 Of the species have been studied. These include almost all of the important forms.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.