16 ELEMENTS OF AGRICULTURE 



made. When pollen from a red flower was applied to the 

 stigma of a white flower, the succeeding generations were 

 just the same as when pollen came from a white flower 

 to the stigma of the red. 



(2) In the first generation the characters did not blend. 

 He did not get a half-wrinkled pea. All were round and, 

 similarly, all had red blossoms. The character that thus 

 appears in the hybrid is called dominant, and the character 

 that is not apparent is called recessive. 



(3) The gametes carried only one of two contrasting 

 characters; otherwise it would not be possible to get a 

 pure red and a pure white from hybrids. This is sometimes 

 called the law of gametic purity. 



If we represent the red color by R and the white by W, 

 a hybrid will be represented by RW. This is what he got 

 in the first generation, but these all appeared red, this 

 color being dominant. When seed from these was planted, 

 the next generation gave three-fourths red and one-fourth 

 white. But, since two-thirds of the red ones produced 

 both red and white in succeeding generations, it is evident 

 that they were hybrids. The proportions may, therefore, 

 be expressed as follows: 



1 R 2 RW 1 W 



One pure red, two hybrids also red, one pure white. The 

 first three all appear alike; the only way to tell their dif- 

 ference being by their action in succeeding generations. 

 A pollen grain of a hybrid is equally likely to carry the 

 red or the white color. On the average, half of them will 

 carry the red and half the white. Similarly, the ovules 

 of a hybrid carry each color. When they unite, we may 



