328 GBOEGE JOHN EOMANES 1893 



natural selection at all in Nature, for the following- 

 reasons. 



Variations are often indefinite in cultivation, 

 especially after several years. Therefore to secure 

 a useful race artificial selection is necessary. On 

 the other hand, variation is definite in Nature, all 

 the seedlings varying in one and the same direc- 

 tion, i.e. towards equilihrium with the environmental 

 forces. Darwin knew of this fact, and you have 

 abundantly described it. But Darwin failed to see 

 that this definite variation in Nature is the rule, and 

 not the exception. Hence, as he admits, natural 

 selection is not wanted at all [i.e. if all variations 

 are definite in Nature]. 



Moreover, it is contended that climatic variations 

 are of no great, even of any useful importance. 

 This may be so, for all I know, with animals ; but it 

 is precisely the reverse with plants. I took my illus- 

 trations from desert plants, and showed that their 

 remarkable characteristics, which give the fades to 

 desert plants, are on the one hand the direct results 

 of the excessive drought, heat, light, &c. On the 

 other, they are just those features which enable the 

 plants' to live under their extremely inhospitable 

 environment. These characters are the minute 

 leaves, hardening of woody tissues, thick cuticle, 

 dense clothing of hair, wax, storage of water tissues, 

 &c. ; so that the whole economy of the plant, in- 

 cluding its specific characters, is all climatically 

 acquired. Although some may vary when the plants 

 are grown in ordinary gardens, such is no more than 

 one would expect on a priori grounds to be the case. 



