PREFACE TO FOURTH EDITION. 



THE; cordial reception given this text is much 

 appreciated by both the author and the publishers. 

 In issuing a fourth edition the chapters have again 

 been carefully reviewed and the known facts to date 

 in elementary histology have been properly recorded. 



The new introduction is written wholly for the 

 elementary student, to arouse in him an interest in 

 the subject matter of the text, and to show the close 

 relation of normal histology to kindred important 

 sciences. The text on spermatogenesis has been 

 enlarged and the known facts stated in as clear and 

 brief a manner as possible. Some of the figures 

 have been replaced with new ones, and minor 

 changes have been introduced throughout the text 

 wherever the subject matter could be improved. 



In this, as well as in former editions, the author 

 has kept in mind his original fundamental purpose, 

 to issue a clear and concise text that could be used 

 as a basis on which the instructor might " build 

 and complete his ideal elementary course in his- 

 tology." 



_ CHARLES Hiu<. 



CHICAGO, lu,.. 



