THE GRASS FAMILY 



169 



Fig. 154. — Longitudi- 

 nal section througli 

 a grain of Maize. 



2. The Grain and its Germination. — The rice grain is a small, 



grayish-yellow thing enclosed in two hairy husks or glumes, the 



larger of which is hve-nerved and sometimes 



terminates in a bristle (awn). The grain 



itself must not be regarded as a seed corres- 

 ponding to that of the Gram or Cucumber: 



it is a fruit consisting of fruit-cover (pericarp) 



and seed, like the achene of the Sunflower; 



but the pericarp is here adnate to the seed. 

 In the seed of the Gram (page 30) we 



have found the plumule lying between two 



thick seed-leaves or cotyledons. The struc- 

 ture of the grain of Rice is 

 quite difterent. Here we have a very small germ 

 at one end of the grain, the remaining part of 

 it being tilled up with a mealy substance, called 

 endosperm. The embryo at the lower end and 

 on the side of the grain does not consist of two 

 cotyledons with the plumule lying between them, 

 but of a small oval body enclosing plumule and 

 radicle. Soak a few grains ^- 

 and cut one of them length- 

 wise. You will then, with 

 the help of a hand-lens, be 

 able to see the 

 --, parts of the em- 



Flg 155.— Youngs Paddy plant. Fig. 156.— Young Gram plant. 



bryo, and as the grains of Maize are larger, the structure of 

 the embryo may easier be seen in that seed. There is a series 



