PLATE 4 
EXPLANATION OF FIGURES 
13. Sixty-seven minutes after insemination. Later stage of sperm amphiaster 
with unequal centrosomes and asters. Double spindle formation between egg 
center and sperm centers. Drawn at stage level with Zeiss 2mm. apochromat 
objective and compensating ocular no. 6. : 
14a and 14h Seventy-seven minutes after insemination. Two successive sec- 
tions of the same egg. The second polar body is just formed. The egg aster is 
beginning to degenerate. The sperm asters are also less developed than pre- 
viously, especially in the case of the smaller one. Sperm amphiaster in 14 a; 
sperm nucleus in 146. Drawn at stage level with Zeiss 2mm. apochromat objec- 
tive and compensating ocular no. 6. 
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