O YMNOaPEBM^. 



405 



the first root of the 

 its whole root sys- 

 tem. The cotyle- 

 dons having thus 

 far been in contact 

 with the e n d - 

 sperm, which fur- 

 nished them with 

 nourishment, now 

 elongate and push 

 out their bases, and 

 in some cases even- 

 tually withdraw 

 themselves entirely 

 from the seed coat 

 (Fig. 300, III.). 

 The apex of the 

 axis' (iDlumule) be- 

 gins a rapid growth, 

 which gives rise to 

 a leafy stem resem- 

 bling that of the 

 parent plant, al- 

 though usually 

 somewhat simpler. 



515.— The tis- 

 sues of the' Gymno- 

 sperms are individ- 

 ually but little high- 

 er than those of the 

 Pteridophytes, but 

 in the mode of their 

 aggregation they 

 present great and 

 important differ- 

 ences, in this latter 

 respect bearing a 

 close resemblance to 

 the tissues of the 

 Dicotyledons among 



new plant, and eventually gives rise to 



Me. 300.— Seeds of Firms Pinea in different stages of 

 germination. 7., ripe seed in longitudinal section ; s, 

 the seed coat ; e, endosperm ; iv, tne hypocotyledonary 

 axis of embryo ; c, cotyledons ; y, the mici-npylar end 

 of the seed, with the root of the emhryo directed to- 

 wards it. 77., 77, four views of the beginning of ger- 

 mination ; A, external view ; if, with half of the seed 

 coat removed ; C, in longitudinal section ; 7>, in. 

 transverse section ; ,?, seed coat ; r, red mi'mhrane lin- 

 ing the seed coat ; e, endosperm ; c, cotyledons ; w, 

 root ; X, ruptured embryo sac. 777, germination com- 

 plete, the cotyledons, c, unfolding, and the hypoctyle- 

 donary stem, he, elongating ; w, the main root, devel- 

 oping lateral roots, ro'.— After Sachs. 



the Angiosperms. The three tissue sys- 



