396 



GARY X. CALKINS AND RACHEL C. BOWLING. 



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FIG. 12. Group of gametes undergoing fusion to form zygotes. Section. 

 Camera lucida. X 900. 



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FIG. 13. Group of zygotes with stages in fusion of the nuclei. Section. 

 Camera lucida. X 1750. 



formation. The two daughter nuclei soon divide again, an 

 inference formed by reason of the comparatively rare occurrence 

 of the binucleated sporoblast. The two nuclei give rise to four 



