PLATE 2 



EXPLANATION OF FIGURES 



9 Primary spermatocyte just before division. 



10 First maturation division. 



11 Spermatid immediately after completion of second maturation division. 



12 Spermatid showing beginning of polarization of the cell as expressed by 

 the aggregating mitochondria (a.m.) and by the manner in which the striated 

 layer is vanishing from the region of the cell which the nucleus is approaching. 



13 and 14 Spermatids in which the process of polarization is continued. 



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