IMPROVEMENTS IN VARIETIES. 323 



when acquired. It will be as well to consider these two 

 subjects separately. 



By what means the first tendency to change their nature 

 was given to domesticated plants, we are entirely ignorant. 

 It is probable that was originally due to accident, and also 

 that it was still mere chance which continued to operate 

 down to very modern times. Philosophers are unacquainted 

 with the reason why there should be any tendency to varia- 

 tion from the characters first stamped on any species by 

 Nature ; but all know that this tendency does exist, and in 

 a most remarkable degree in many species. There is in 

 all beings a disposition to deviate fiom their original nature 

 when cultivated, or even in a wild state ; but this disposition 

 is so strong in some as to render them particularly well 

 adapted to become subject to domestication : for instance, 

 the dog, the pigeon, and the barn-yard foul, are cases in 

 which this tendency is most strongly marked in animals ; 

 and domesticated fruits are a parallel case in the vegetable 

 world. 



Without, then, vainly endeavouring to discover the first 

 cause of this disposition to form varieties, let us take it as a 

 naked fact that the disposition exists. Cultivators increase 

 this disposition chiefly in two ways : either by constantly se- 

 lecting the finest existing varieties for seed, or by intermix- 

 ing the pollen and stigma of t'.vo varieties for the purpose of 

 procuring something of an intermediate nature. The an- 

 cients Vv'ere unacquainted with either of these practices, and 

 consequently their gardens contained few things which 

 would now be deemed worthy of cultivation. The povrer 

 of obtaining cross-bred varieties at pleasure has only ex- 

 isted since the discovery of sexes in plants ; but as it exerts 

 a most extensive influence over alterations in the vegetable 

 iungdom, it may be considered the most important control- 

 ing power that we possess. 



In sowing seech for the purpose of procuring improved va- 

 rieties, care should be had, not only that the seeds be taken 

 from the finest existing kinds ; but also that the most hand- 

 some, the largest, and the most perfectly ripened specimens 

 should be those that supply the seed. A seedling plant will 

 always partake more or less of the cb.aracter of its parent, 

 the qualities of vvliich are concentrated in the embryo when 

 it has arrived at full maturity. How this concentration takes 

 place, we are as ignorant as why certain constitutional pe- 

 culiarities are in men transferred from father to son, and 



