24 



THE VEGETATIVE ORGANS 



fruit (Fig. 9, i) is a different type. Examine its curious, 

 slightly-twisted, and winged fruit-case (i), which is swollen 

 at one end and contains a single seed. Cut open the fruit- 

 coat (2 pe) and notice the mode of attachment of the 

 seed (2 ju) ; then remove the seed-coat and examine 

 the contents. Split open the seed, and between the two 

 flat lobes you will find the embryo, consisting of a radicle 

 (2 ra), above which are the two cotyledons (2 c), having 



Fig. 9. Fruit of Ash. 1, side view ; 2, fruit opened and seed 

 dissected ; c, cotyledon ; e, endosperm ; ju, funicle ; pe, pericarp ; 

 ra, radicle ; /, testa. 



between them a very small plumule. This seed contains 

 not only an embryo, but, in addition, two large lobes (e) 

 stored with food-materials. Such food-reserve stored out- 

 side the embryo is called endosperm, and the seed is said 

 to be endospermous (Gr. endon = within, s per ma = seed) . 



Plants similar to the above, which contain two cotyle- 

 dons in the embryo, are placed together in a large class 

 called Dicotyledons. 



Germination. Growth of root and shoot. Let us now 



