MORPHOLOGY 



(iii) If the point of a penknife or a pin be inserted opposite to the 

 hilum, the seed-coats can be removed. The seed-coat, or Spermoderm, 

 consists of two layers ; the outer is known as the testa, anuthlT'Tfiner 

 is called the tegmen. 



(iv) The seed-coats surround a whitish mass, which may fall in pieces ; 

 this is the young plant or embryo. 



(v) If the embryo is examined there will be found along the side near 

 to the micropyle a small body, called the radicle, the apex of which 

 points towards the micropyle. 



(vi) Now separate the white mass, along the middle line, into its two 

 divisions the sed-leaves or cotyledons. 



(vii) Between the cotyledons will be found the plumule or young 

 stem, which is continuous with the radicle, and if you use a lens 



FIG. 5. Bean Seed. A = A side view of seed. B = Showing radicle. C = Bean, 

 with seed coats stripped off. D = Seed coats. E = The two cotyledons. 

 F = Plumule/ 



you will be able to see a number of minute leaves growing from the 

 plumule. 



(viii) It care be taken in examining the embryo, it will be noticed 

 that the radicle, plumule, and cotyledons are all joined together to form 

 the body of the embryo. 



We can represent the relations of the parts of the bean seed 

 as follows : 



Bean. 



Radicle, 



or young root, or seed leaves, or young stem. 



Structure of a Grain of Wheat. 



EXPT. 3. Take a few grains of Indian Corn, and soak them in 

 water for a few hours, and examine in the following way : Cut the 

 grain lengthwise with a sharp knife, and look at half of it with a hand 

 lens. Observe 



(i) The covering, which is made up of several layers, only two of 



