364 Mr. T. A. Knight on esculent Strawberries. 



posed species of each of the preceding; genera would, I am very 

 confident, be found capable of breeding with, and being trans- 

 muted into, each other, as to their external characters; and if' 

 botanical writers still choose to call such species, they ought cer- 

 tainly to distinguish them from others, as secondary or trans- 

 mutable species. The external form and character of each planv, 

 as it came from the hand of nature, was probably sufficiently 

 peculiar to render it readily distinguishable from those of every 

 other species : but varieties of soil, of climate, and of culture ap-i 

 plied for other purposes, have so far mixed and confounded the 

 primary characteristics of many species, that experiments, such 

 as those above described, now afford probably the only source of 

 decisive evidence. 



XXIV. On 



