MAN AND THE BIOLOGICAL WORLD 



Copyright, 1942, 1952, by the McGraw-Hill Book Company, Inc. Printed in 

 the United States of America. All rights reserved. This book, or parts thereof, 

 may not be reproduced in any form without permission of the publishers. 



Library of Congress Catalog Card Number: 51-12946 



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MAPLE PRESS COMPANY, YORK, PA. 



