Latent Characters 243 



ferent countries from the same species. The 

 repetition obviously indicates a common inter- 

 nal cause. The white varieties of blue- and red- 

 flowered plants occur in the wild state so often, 

 and in most of the instances in so few in- 

 dividuals that a common pedigree is absolutely 

 improbable. In horticulture this tendency is 

 widely and vexatiously known, since the repeti- 

 tion of an old variety does not bring any ad- 

 vantage to the breeder. The old name of 

 " conquests," given by the breeders of hya- 

 cinths, tulips and other flower-bulbs to any 

 novelty, in disregard of the common occurrence 

 of repetitions, is an indication of the same ex- 

 perience in the repeated appearance of certain 

 varieties. 



The rule of parallel variations demands that 

 the same character occasionally makes its ap- 

 pearance in the several varieties or races, de- 

 scended from the same species, and even in 

 widely distinct species. This is a rule, which 

 is very important for the general conception of 

 the meaning of the term variety as contrasted 

 with elementary species. For the recurrence 

 of the same deviation always impresses us as a 

 varietal mark. Laciniated leaves are perhaps 

 the most beautiful instance, since they occur in 

 so many trees and shrubs, as the walnut tree, 

 the beech, the birch, the hazelnut, and even in 



