GINKGOALES 213 



large mucilage cavities are abundant in the cotyledons. The mature 

 embryo usually has five leaves, the first two of which are decussate 

 with the cotyledons, while succeeding leaves in the embryo and 

 seedling are irregular in their arrangement (fig. 231 C, D). 



Fig. 230. — Ginkgo blloba: embryo at stage in which three regions are recognizable. 

 The stem and root will be organized from the small-celled tissue; X 160. — After Lyon.''" 



Seeds germinate readily, the terminal part of the cotyledons re- 

 maining inside and enlarging considerably. They gradually absorb 

 all of the female gametophyte and pass it on to the growing seedling. 

 There is a strong tap root, and the leaves are deeply lobed (fig. 232). 



