GROUP IV. — PHANEROGAMIA : GYMNOSPEKM^. 



473 



FiQ. 299.— Later stages in the embryogeny of the sporopbyte of Picea exceUa (after 

 Strasburger). A Optical section of young embryo borne on the end of the suspensors ( x 240) : 

 B older embryo, with suspensor and embryonal tubes ; iit this btage the growing-points of 

 primary root and stem are already differentiated : C half-grown embryo in surface-view : 

 D longitudinal section of a half-grown embryo : E surface-view of the apex of the shoot of 

 this embrj'o ( x 27) : F longitudinal section of a fully developed embryo in a ripe seed ; c 

 cotyledons; h hypoctyl; pi apex of the plerome in the root; cp root- cap ; mpith; op pro- 

 cambial ring. 



