362 



JORDAN. 



PLATE XVI. 



Figs. 24-25. Views of upper pole of living egg ; first two cleavage planes. 

 Figs. 26A-26D. One egg seen from different points of view. 26A, upper 

 pole ; 26D, lower pole. 



Figs. 27A-27D. One egg from different points of view. 



27D, lower pole. 



Figs. 28A-28D. 

 28D, lower pole. 



Figs. 29A-29D. 

 29D, lower pole. 



Figs. 30A-30B. 

 30B, lower pole. 



Figs. 31A-31B. 



Figs. 32A-32B. 



One egg from different points of view. 

 One egg from different points of view. 

 One egg from different points of view. 



27A, upper pole ; 

 28A, upper pole ; 

 29A, upper pole ; 

 30A, upper pole ; 



Upper (31 A) and lower (31 B) pole views of one egg. 

 Upper (32A) and lower (32B) pole views of one egg. 



Fig. 33A. Upper pole of living egg, four hours and three-quarters after the 

 appearance of first cleavage plane ; i-i, first plane; 2-2, second. 



Fig. 33B. Same egg, ten minutes later than Fig. 33A. 



Fig. 33C. Lower pole of same egg, one hour later than Fig. 33A. 



Fig. 33D. Upper pole of same egg, two hours later than Fig. 33A. 



Fig. 33E. Lower pole of same egg, thirty minutes after Fig. 33D. 



Fig. 33F. Upper pole of same egg, fifty minutes after Fig. 33D. 



Figs. 26A-32B were drawn with the camera from preserved specimens. All 

 X 20. The heavy lines indicate the position of the first two cleavage planes. 



Figs. 33A-33F were drawn freehand from the successive stages of a living egg. 

 The first two cleavage planes are designated by heavy lines, the third set by long 

 dashes, the fourth by short dashes, and the fifth by light full lines. 



