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ces of opinion still to exist among them, unless the distinctions and 

 limits of species were truly very uncertain — not to write, arbitrary. 



The preceding examples are derived from plants in a state of na- 

 ture. When brought under cultivation, and it becomes the interest 

 or amusement of cultivators to increase and extend their variations, 

 scarce any limit can be set upon the power of doing so. Our culti- 

 vated species of Pelargonium, Erica, Rosa, Fuchsia and Calceolaria, 

 have now become respectively an undistinguishable intermixture of 

 cross breeds and varieties. The changes brought about in long-cul- 

 tivated fruits and vegetables seem to prove that varieties of a single 

 species may differ quite as widely among themselves, as do other 

 plants which are usually accounted distinct species. We have exam- 

 ples in the apple, pear, plum, gooseberry, strawberry and grape, 

 among fruits ; in the pea, potato and cabbage, among vegetables. 

 To these we might add olher examples in florists' flowers ; such as 

 the Dahlia and pansy, which have been so greatly run into varieties 

 in the course of a few years past. 



The numerous and still increasing variations in the species above 

 mentioned, afford clear proofs that the progeny is not necessarily a 

 copy of the parent, varying only in luxuriance or other slight and 

 temporary character. In the coiu'se of generations some descendants 

 differ so widely from their ancestral plants, as to appear like distinct 

 species, when they are contrasted against other less changed, or un- 

 changed, descendants from the same ancestors — or, at least, what are 

 supposed to be such. We find, indeed, a conflict of opinion in some 

 cases, whether the wild and the cultivated species have been derived 

 from the same common stock, or whether they have been aboriginally 

 distinct. Let us make a short series, in example of this, where the 

 uncertainty respecting an original identity of stock will become great- 

 er and greater. It is generally agreed, I believe, that the wild thorny 

 pear is the original stock of all our garden pears, various though they 

 are. It is not quite so generally allowed, that the wild thorny crab 

 of our hedge-rows is the true stock of the garden apples in their count- 

 less varieties. More doubt attaches to the wild sloe or the bullace (or 

 both, as two forms of a single species) in the light of a common stock 

 to all our plums of the garden. And very few botanists seem prepared 

 to receive the wild cherry [Prunus Cerasus) as the real stock of the 

 garden cherry {Prunus avium). Some of our Cerealia cannot be re- 

 ferred to any known wild stock; whether the original species has 

 ceased to exist in a state of nature, or whether the long-cultivated va- 

 rieties have lost resemblance to their original stocks, might be made 



