EMBRYOLOGY OF PICEA. 



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FIG. 138. Picea vulgo.ris. A, young rudimentary embryo in optical section (x 

 ^240). B. older rudimentary embryo in optical section. The rudimentary root and 

 growing point of the stem are already formed (x 27). G. half-ripe embryo seen from 

 the outside. Z>, the same in longitudinal section. E. in apical view (x 27). F, 

 longitudinal section through a ripe seed, showing : c, cotyledons ; h, hypocotyl ; pi, 

 apex of the plerome of the root ; c/j, root-cap ; cl, its central column ; in, pith ; op, 

 procambial ring in the hypocotyl (x 10). 



