550 STRUCTURE AND LIFE HISTORIES 



Mendel, a monk in the monastery at Briinn, Austria, where 

 he finally became abbott. In order to understand his 

 work clearly the student should examine carefully the 

 structure of the edible or garden pea, the chief plant with 

 which Mendel worked. 



469. Mendel's Problem. It was a favorite study of 

 Mendel's to hybridize (i.e.j cross-pollinate) plants of differ- 

 ent species and varieties, and observe the behavior of the 

 resulting hybrids in successive generations. The problem 

 which he endeavored to solve was the law or laws "gov- 

 erning the formation and development of hybrids/' 1 with 

 special reference to the laws according to which various 

 characters of parents appear in their offspring. 



470. Mendel's Method. He recognized that, in order 

 to solve the problem, attention must be given to at least 

 three points, as follows: 



1. "To determine the number of different forms under 

 which the offspring of hybrids appear." 



2. "To arrange these forms with certainty according to 

 their generations." 



3. "To ascertain accurately their statistical relations," 

 that is, to express the results quantitatively. 



No previous student had recognized the fundamental 

 importance of these requirements. 



471. Choice of Material. Mendel realized that the 

 success* of any experiment depends upon choosing the 

 most suitable material with which to experiment. He 

 laid down the requirements as follows: 



1 All the quotations in this chapter are from an English translation of 

 Mendel's original paper. His form of expression has been preserved 

 as far as possible, even when the "quotes" are omitted. 



