Description of Some New Species of Invertebrates From the Palaeozoic Rocks of Illinois and Adjacent States (Classic Reprint)

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Excerpt from Description of Some New Species of Invertebrates From the Palaeozoic Rocks of Illinois and Adjacent StatesAmbulacral areas as wide in the middle part, and wider toward the poles than the interambulacral areas, and separated in each ambulacral field the entire length by a sharply defined ridge elevated as high as the interambulacral areas. The plates are smaller and more irregular in the ambulacral depressions than elsewhere. The ambulacral pores are circular, two in each plate, and form four irregular ranges of pairs in each depres sion. When the two each ambulacral area, unite near the ocular plate there are five or six rows of pores. The small plates are pierced with the ambulacral pores until they actually abut upon the little ocular plates.Three pores are clearly distinguishable, in some of the genital plates, with an ordinary magnifier, and there are some evidences of other pores that have been closed or filled up. 'there are no pores in the ocular plates. The plates abutting the oral open ing are angular and preserve the articulating edges of the oral plates.Found in the St. Louis Group, at Greenville, Harrison county, Indiana, and now in the collection of Wm. F. E. Gurley.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.