PLATE 3 



EXPLANATION OF FIGURES 



17 to 28 From normally fertilized eggs. 



17 Telophase, first cleavage. 



18 Two-c«ll stage. 



19 to 21 Formation of three-cell stage. 



22 Formation of four-cell stage directly from two-cell stage. 



23 and 24 Three-cell stage. 



25 Four-cell stage. 



26 Middle cleavage stage. 



27 Nine hours after fertilization. 



23 Twenty-four hours after fertilization. 

 2"> to 31 From parthenogenetic eggs. 



20 Telophase, first cleavage. 

 30 and 31 Two-cell stage. 

 Magnification, 575 diameters. 



40 



