3O2 ELIZABETH A. SMITH. 



PLATE VI. 

 Libellula basalt!. 



FIGS. 107, 108 AND 109. Primary spermatocyte stages (X 1,500) from fresh 

 material. 



FIGS, no, in, AND 112. Telophases of primary spermatocyte division. 



FIG. 113. Telophase of primary spermatocyte division from aceto-carmine 

 smear. 



FIGS. 114, 115. AND 116. Polar view? of chromoFomes of secondary spermato- 

 cytes. 



FIG. 117. One chromosome apparently going to one pole undivided in second- 

 ary spermatocyte division. 



FIG. 1 1 8. Sex-chromosome lagging behind in secondary spermatocyte division. 



FIGS. 119, 120, 121, 122, AND 123. Various stages in secondary spermatocyte 

 division. 



FIGS. 124-128 INCLUSIVE. Spermatozoa drawn from living material. 



