ANGIOSPEBMS 

 c 



345 





FIG. 203. Development of the ovule and embryo of shepherd's purse (Capsella) 



A-C, stages in the development of the ovule ; n, nucellus of megasporangium ; ii and 



ol, inner and outer integuments ; m, micropyle ; es, embryo sac ; //, mature ovule 



(megasporangium) with emhryo sac, embryo (em), and endosperm nuclei (e); D~G, 



stages in the development of the embryo ; s, suspensor ; r, root ; c, cotyledons 



nuclei, and the antipodal cells. The student will note at once 

 the great difference between this reduced gametophyte of the an- 

 giosperms and that of the cycads and spruce. In the angiosperm 

 the female gametophyte consists of six cells and two nuclei, 



