142 ALICE M. BORING. 



EXPLANATION OF PLATE II. (Philcenus spumarius). 



FIGS. 10, u. Two optical sections of one primary spermatocyte spindle such 

 as is represented in Fig. 12, odd chromosome toward one pole. 



FIGS. 12, 16. Two metaphase spindles of the primary spermatocyte division. 



FIGS. 13, 14. Early and late growth stages of the primary spermatocyte. 



FIG. 15. Prophase of the primary spermatocyte, odd chromosome the only 

 univalent one. 



FIG. 17. Anaphase of the primary spermatocyte division, odd chromosome 

 toward one pole. 



FIG. 1 8. Two daughter plates of a primary spermatocyte division, each with 

 II chromosomes, the odd chromosome between them. 



