STRUCTURE OF THE SEED. 

 Fig. 112. Fig. 113. 



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Fig. 112. a shows theexorhizal germination of the Dicotyledonous seed of the orange; 

 c, the cotyledon; g, the first pair of aerial leaves; r, the radicle naked and without a 

 eheath. 



Fig. 113. Seed of oats sprouting.' r, roots passing through the sheath, sh, from the 

 single cotyledon c. g, The young leaves and stalk. 



to it, and which it raises with it above the earth, when its 

 elongation operates from its base. 



The cotyledons. These are the lateral appendages of the 

 embryo axophyte. The cryptogamia have no cotyledons in their 

 embryos, which are therefore acotyledonous. The embryo in 

 such cases is called a spore, and as it gives off roots indiffer- 

 ently from any part of its surface, and from a fixed point, it 

 is termed heterorizal, (stspos diverse.) Plants possessing coty- 

 ledons in their embryo are termed cotyledonous. If we examine 



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