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' » ^^ Ten chromosomes 

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Ten chromosomes 

 of female oyster 

 gamete 



Figure I. — The coming together on the tlrst cleavage spindle of 

 the 10 chromosomes of the male and 10 chromosomes of the 

 female gamete of the American oyster. Crassostrea virginicci. 







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*d 



r 



V 



Figure 2. — The 10 pairs of chromosomes of the mature, spawned 

 egg of the American oyster. Ciass<ntie<i virf;iiuc(i. 



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a 



