240 PLAIN AND PLEASANT TALK 



several among them vary, some more and others less, and 

 wlien they have once departed from tlieir natural state, 

 they never again retm-n to it, but are removed more and 

 more therefrom, by successive generations, and produce, 

 sufficiently often, distinct races, more or less durable, and 

 that finally if these variations are even carried back to the 

 territory of their ancestors, they will neither represent tlie 

 character of their parents, or ever return to the species 

 from whence they sprung." 



Accordingly, Van Mons began to sow the seeds of natural 

 and wild fruit which were in a variable state. By all means 

 within his power he hastened his seedlings to show fruit. 

 The first generation showed only poor fruit but decidedly 

 better than the wild. Selecting the seed of the best of 

 these, he sowed again. From the fruit of these he sowed 

 the third generation. From the third, a fourth ; and from 

 the fourth, a fifth ; as far as the eighth generation. 



His experience showed that there was great diflference 

 among different species of fruit in the number of gene- 

 rations through which they must pass before they were per- 

 fect. The apple yielded good fruit in the fourth genera- 

 tion. Stone fruits produced perfect kinds in the third 

 generation. Some varieties afforded perfect fruit in the 

 fifth generation, while others go on improving to the 

 eighth. 



The time required for this renovation diminished at each 

 remove from the normal or wild state. Thus, the trees 

 from the second sowing of the pear-seed fruited in from ten 

 to twelve years ; those from their seed, or of the third gene- 

 tion in from eight to ten years ; those of the fourth genera- 

 tion in from six to eight years ; those of the fifth genera- 

 tion, in six years, and those in the eight, in four years. 

 These are the mean terms of all his experiments. 



To obtain perfect stone fruits, through four successive 

 generations, from parent to son, required from twelve to 

 fitleen years ; the apple required twenty years, and the pear, 



