152 MARY J. GUTHRIE AND HOPE HIBB.^D. 



EXPLANATION OF PLATE II. 



FIG. 7. Side view of 8-celled stage. 



FIG. 8. Side view of i6-celled stage showing the micromeres cut oft" at the 

 vegetal pole. 



FIG. 9. View of i6-celled stage from vegetal pole. 



FIG. 10. View of 32-celled stage from vegetal pole showing second set of 

 micromeres. 



FIG. 11. Side view of 32-celled stage. 



FIG. 12. Polar view of a 76-celled stage showing f he twelve micromeres. 



