PLATE XLVIII. 

 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 is much 

 longer than normal, is central in the egg and the spindle fibres, centrosomes and astral rays are either lacking 

 or very faint. The position is probably due to pressure. 



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

 in position, 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, 

 the other containing two nuclei and one sphere, probably as the result of pressure at the close of the 1st 

 cleavage. 



Fig. 74. Exp. 1121 (2): Second cleavage spindle abnormal in position and division delayed in one 



blastomere. 



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

 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 eight 

 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 the 

 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 of 

 micromeres, showing effects of pressure. 



