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INTRODUCTION TO EMBRYOLOGY OF ANGIOSPERMS 



Figure 117C shows two fertilized eggs in division, one in prophase 

 and the other in metaphase. 



A couple of instances of fertilization of antipodal cells are also on 



#7/ 



D 



Fig. 116. Some abnormalities of fertilization in Sagittaria graminea. A, upper 

 part of embryo sac, showing egg-like synergids, egg, and upper polar nucleus. B, 

 embryo sac, showing double fertilization (spi = male gamete fusing with egg; sp 2 = 

 male gamete fusing with polar nuclei); note second pollen tube with another pair 

 of male gametes (sp s , sp 4 ). C, first division of primary endosperm nucleus com- 

 pleted; nucleus of zygote in metaphase. D, part of fertilized embryo sac, showing 

 two-celled proembryo, and two male gametes attached to two endosperm nuclei. 

 E, three two-celled proembryos, two of which have probably arisen from fertilized 

 synergids; note two pollen tubes. (After Johri, 1936a.) 



record. Derschau (1918) reported the fusion of two sperms with 

 an antipodal cell in Nigella arvensis, and judging from the state- 

 ments of Shattuck (1905) and Ekdahl (1941) it seems probable that 



