PLATE XLVIIL 



Effects of Electric Current. 



Eggs subjected to electric current (except figs. 76, 77) but probably showing effects of pressure 

 Fig. 68. Exp. 1104 (?): 5 mil. amp., 5 min. First maturation spindle; the mitotic figure i 



very 



normal, is central in the egg and the spindle fibres, centrosomes and astral 

 t. The position is probably due to pressure. 



spindles abnormal 



Fig. 69. Exp. 1121 (2): 5 mil. amp. 10 min., normal 3£ hrs. Second cleavage 



osition, first cleavage furrow incomplete, development stopped. 



Fig. 70. Exp. 1121 (2): Similar to preceding. 



Fig. 71. Exp. 1121 (2): Similar to preceding. 



Fig. 72. Exp. 1121 (2): Similar to preceding. 



Fig. 73. Exp. 1121 (2): Two cells, one containing a complete amphiaster but without any chromatin 



cleavage. 



and one sphere, probably as the result of pressure at the close 



Fig. 74. Exp 

 blastomere. 



spindle abnormal in position and division delayed 



Fig. 75. Exp. 1121 (2): Three macromeres in a linear series, the middle one containing two separat* 

 cytoplasmic areas, nuclei and spheres, the result of the suppression of the first cleavage, as in fig. 72. 



Fig. 76. Exp. 1001 (3): A pressure experiment included in this plate by mistake, showing eigh 

 macromeres and eight micromeres. 



Fig. 77. Exp. 919: Egg subjected to pressure, probably after formation of 1st set of micromeres 

 In quadrant B and D the 2d set of "micromeres" are really macromeres. 



Fig. 78. Exp. 1110 (2): 5 mil. amp., 2 min., normal 22 hrs. Egg with scattered blastomeres in th< 

 stage of the formation of the 2d set of micromeres. 



Fig. 79. Exp. 1121 (3): 5 mil. amp., 10 min., normal 16 hrs. Egg in stage of formation of 2d set o 

 micromeres, showing effects of pressure. 



