Excerpt from Studies on North American Polystomidae, Aspidogastridae, and Paramphistomidae: With Eleven Plates The knowledge of the trematodes of North America is very scanty. Information at hand consists largely of brief and scattered papers and comprehensive studies on the morphology of the larger groups are want ing. Such studies are needed as contributions to the lmowledge of adult forms, and it is apparent also that knowledge of the anatomy and tax onomy of the adult is demanded in the solution of life history problems. 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.