THE MATURATION OF THE EGG AND OVULATION 

 IN THE DOMESTIC CAT 



W. H. LONGLEY 



From the Sheffield Biological Laboratory of Yale University 



THIRTEEN FIGURES 



CONTENTS 



Introduction 139 



The egg of the cat 141 



Material and method 141 



Sexual season 144 



Ovulation 145 



Maturation and pairing 153 



The ovarian egg at the end of the period of growth 156 



The first polar spindle 158 



The first polar body 161 



The second polar spindle 162 



Fertilization . . 163 



The second polar body 164 



Pronuclei 165 



Cleavage 165 



Summary 166 



Bibliography 167 



INTRODUCTION 



Knowledge of the essential nature of the maturation of the 

 germ cells, of fertilization and of cleavage was won chiefly from 

 the study of invertebrates, although Van Beneden ('75), studying 

 the rabbit, upon some points anticipated the brilliant results 

 of the researches of Oscar Hertwig ('75-' 78). 



Employing improved cytological methods and with very abund- 

 ant material for study, Sobotta ('95) published in full the results 

 of an investigation upon the egg of the mouse, which established 



THE AMERICAN JOURNAL OF ANATOMY, VOL. 12, NO. 2 



139 



