274 MARY T. HARMAN. 



PLATE II. 



FIG. 13. Primary spermatocyte chromosomes showing the beginning of the 

 formation of the vesicles. 



FIG. 14. Primary spermatocyte chromosomes in vesicles. 



FIGS. 15 AND 16. Metaphase, lateral view, of first spermatocyte division. The 

 accessory chromosome is at the periphery of the spindle. 



FIGS. 17 AND 19. Metaphase plates of first spermatocyte division showing 

 seven chromosomes. 



FIG. 18. Metaphase plate of first spermatocyte division showing six chromo- 

 somes. The accessory chromosome is not in the metaphase plate. 



FIG. 20. Beginning anaphase of first spermatocyte division. 



FIG. 21. Late anaphase of first spermatocyte division showing seven chromo- 

 somes. 



FIG. 22. Metaphase, lateral view, of second spermatocyte division showing 

 seven chromosomes. 



FIG. 23. Metaphase plate of second spermatocyte division showing seven 

 chromosomes. 



FIG. 24. Metaphase plate of second spermatocyte division showing six chromo- 

 somes. 



