THE FEMALE GAMETOPHYTE 



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C D 



Fig. 70. Some stages in development of embryo sac of Peperomia hispidula. 

 A, eight-nucleate embryo sac; nuclei shown in dotted outline have been included 

 from adjacent sections of sac. B, l.s. ovule, showing 16-nucleate embryo sac. C, 

 embryo sac, showing egg, one synergid, and 12 polar nuclei. D, embryo sac with 

 egg, single synergid, and large lobed secondary nucleus. (After Johnson, 1914-) 



