PRENTICE HALL ANIMAL SCIENCE SERIES 

 H. Burr Steinbach, Editor 



Copyright, 1953, by 



PRENTICE HALL, INC. 



70 Fifth A\'enue, New York 



All rights reserved. No part of this book mav be repro- 

 duced in any form, by mimeograph or any other means, 

 without permission in writing from the publishers. 



L.C. Cat. Card No.: 52-14030 



PRINTED IN THE UNITED STATES OF AMERICA 



