DEVELOPMENT AND STEUCTUEE. 



THE vital principle of maize is lodged in the em- 

 bryo, or rudiment, a small, clearly defined interior 

 division of the seed, or kernel. This embryo is the 

 starting point of life and growth. It extends from 

 the base of the grain upward, about two-thirds of the 

 distance toward the crown, and lies in contact with 

 the epidermis on one side of the kernel, through 

 which it can be distinctly traced by the eye. 



The earliest movement of the seed in developing 

 the new plant is termed germination. When the 

 plant has advanced so as to form leaves that contrib- 

 ute to its growth, the process is termed vegetation. 



Three conditions are essential before germination 

 can take place. The presence of heat,* moisture, and 

 air is indispensable. After the seed is planted, and 

 these agents have had time to exert their quickening 

 influence, a small root shoots out, with a very rapid 

 growth, from the base of the embryo, and, after 

 another interval, the stem rises slowly from its apex. 



* 48 Fahr. is about the limit of temperature, below which corn will 

 not germinate. 



