Climate on Plants and Animals. 123 



of species 1 I suppose the phrase, gradation of being, is 

 often used with too much looseness, and hence it frequently 

 happens that confusion results from its use ; and it undoubt- 

 edly arises from misunderstanding the nature of the changes 

 which have taken place in some species, and especially those 

 which are represented by numerous varieties. These varieties 

 are never generic, but strictly specific. Take the apple, which 

 runs into many varieties ; those varieties all retain the charac- 

 teristics of the species. No apple has been found yet which has 

 made the least progress towards the pear ; neither has the 

 pear yet transformed itself, nrany of its varieties, into an apple ; 

 each and every one of them are equally removed from the 

 genus, and yet each branches out into hundreds of varieties ; 

 and no one has the least doubt to which species any one of 

 the varieties belong. The same is true of all the other 

 species. There is no upward or downward movement in this ; 

 there is, it is true, in the case of fruits, a difference in quality, 

 but none of them can be said to have made any progress to- 

 ward an allied species. The constitutive power to multiply 

 varieties is only a part of their specific characters. If we 

 turn our thoughts to the animal kingdom for illustration of 

 the same principle, for example, we find the elephant is apt 

 to learn, while the rhinoceros or hippopotamus rarely possess 

 this aptitude in the smallest degree ; the positive character 

 of the first is as important specifically, as the negative in the 

 latter. If, then, by gradation of character, it is designed to 

 convey the idea that species coalesce, by the resemblances in 

 their varieties, the idea is erroneous ; if, however, the phrase 

 is designed to convey or express the fact, that in the system 

 to which they belong, some species occupy a higher position 

 than others, or that there are grades of development, some of 

 which are high and others low, it is undoubtedly true. The 

 position which a species holds is positive and arbitrary ; 

 species occupy a shelf or platform which is fixed, and it neither 

 inclines downward nor upward ; the position of the shelf, or 

 in otherwords, the species, isnearer one than another species, 

 that is, a species more closely resembles certain species than 

 others. Although the distance between neighbouring species 

 is unequal, still the two which are nearest akin never coalesce 



