112 



MORPHOLOGY OF AXGIOSPERMS 



Sparganium), but they are not associated with an invasion of 

 the chalazal region, and simply receive material from it. This 

 type is characteristic of Monocotyledons (except Gramineae) 



Starch (abundant). 



Do. (scanty). 



Dextrine. 



Cuticularized membranes. 



Fig. 52. — Tricyrtis hirta. Various stages in development of ovules, embryo-sac, and 

 embryo, showing the starch, dextrine, and cutinized membranes at different periods, 

 the sequence being indicated by the letters A-G. — After Ikeda. 106 



and Archichlamydeae (except many Amentiferae). In the 

 aggressive type, active and often multiplying antipodal* are 

 associated with the penetration of the chalazal region by the 



