PLATE 4 



EXPLANATION OF FIGURES 



46 Early second spermatocyte, showing the breaking up of the telophase 

 chromosomes. Position of spindle remains typical. 



47 Resting stage of second spermatocyte. 



48 Same as the preceding, the chromatic nucleolus found in only half the cells 

 of the second spermatocyte. 



49 Early prophase of second spermatocyte. 



50 Same as the preceding, chromatic nucleolus double. Ring of mitochondrial 

 granules around the nucleus. 



51 Resting stage of second spermatocyte, showing formation of spindle 

 fibers before the prophase stage is reached. 



52 Side view metaphase of second spermatocyte. 



53 Eighteen chromosome metaphase plate of the second spermatocyte. 



54 Side view metaphase plate of second spermatocyte. Rod centrosomes 

 with granules at inner ends. 



55 Early anaphase of second spermatocyte with the autochromosomes divid- 

 ing longitudinally, while the idiochromosomes have separated transversely. 



56 Metaphase plate of second spermatocyte. The sixteen chromosome type. 



57 Later anaphase of second spermatocyte. 



58 Same as the preceding with granules at poles instead of rods. 



418 



