ELEMENTARY BIOLOGY. [CHAP. 



7. The small passage (micropyle) leading through 

 the coats down to the nucleus. 



S. In some specimens, a large cavity (the 

 embryo-sac] will be seen in the nucleus just 

 opposite the micropyle. In the embryo-sac 

 may be seen some small granular cells (the 

 embryo-cell and endosperm cells). 



f. The seeds. 



Soak some dried beans in water for twenty-four 

 hours ; they will slightly swell up and be more readily 

 examined than when dry. 



a. Note the black patch on one end of the bean, 

 marking where the stalk (funiculus) which fixed 

 it in the pod was attached to it. 



b. Having wiped all moisture off the bean gently 

 press it while observing that part of the black 

 patch which is next its broader end : close to 

 the patch a minute drop of fluid will be observed 

 to be pressed out through a small opening, the 

 micropyle. 



c. Carefully peel off the outer coat (testa) of the 

 seed : the two large fleshy cotyledons will be 

 laid bare. 



d. Joining the cotyledons together will be found 

 the rest of the embryo : it consists of a conical 

 part (the radicle) lying outside the cotyledons, 

 with its apex directed towards the point where 

 the micropyle was; and of the rudiments of 

 the stem and leaves (plumule) lying between 

 the cotyledons. 



