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W. E. HOY, JR. 



EXPLANATION OF PLATE III. 



D iabrotica. 



Fig. 9. Ectoderm, 21 chromosomes. 



FIG. 10. Neuroblast, 21 chromosomes. 



FIG. ii. Ectoderm, 22 chromosomes. 



FIG. 12. Tetrads of first maturation division of the egg. 



