228 INFLUENCE OF CLIMATE ON PLANTS AND ANIMALS. 



sometimes it operates, in other locations where the climate is modified, to restrain development 

 and perfection. Climate never intermeddles with specific characters ; it may, for a time, ob- 

 scure those characters in a monstrous growth, when aided by a rich soil, or by overfeeding. 

 A problem of great importance may be solved by observing what products are specially 

 favored by certain climates, and what climates are unfavorable to the production of the same. 

 Where we have climate in our favor, and have not to contend with it, the expense of production 

 is materially diminished ; the certainty of the product is also increased, and its perfection se- 

 cured, by which its value is also increased. As an element of climate the temperature of the 

 soil at different depths is one of great importance The different soils may be said to enjoy 

 different climates ; those which are sandy possess a climate unlike that of a clay soil ; a due 

 admixture of sand and clay would combine elements which belong to a climate intermediate 

 between the two. 



In pursuing our investigation in regard to species and varieties, it is highly important that 

 we should be impressed with the fact that specific characters are permanent, and it will appear, 

 on reflection, that this is a beautiful and wise arrangement There is a fitness in the provision 

 of individualizing species, as it were, both by corporeal marks and by intellectual and in- 

 stinctive power. The intention or purpose which is fulfilled by this arrangement I do not in- 

 tend to speak of now, it is the fact which I wish to bring before the reader. Many persons, 

 however, when they speak of gradations of character, and of the intimate relations of things, 

 and the links which bind all together, seem to labor under a fallacy. Where are those grada- 

 tions seen, and what is the idea which is thus prominently set forth ] What are the gradations 

 of being 1 Is it probable that in the gradations which are insisted upon that there is any thing 

 like a coalescence of species 1 I suppose that 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 

 undoubtedly 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 varie- 

 ties are never generic, but strictly specific. Take the apple, which runs into many varieties : 

 those varieties all retain the characteristics 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, in 

 any 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 belongs. The same is true of all other species. There 

 is no upward or downward movement in this ; there is, it is true, in the case of fruits, a dif- 

 ference in quality, but none of them can be said to have made any progress towards 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 exam- 

 ple, we find the elephant is apt to learn, while the rhinoceros or hippopotamus scarcely pos- 

 sesses 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 erro- 



