76 ALPINE AND ARCTIC PLANTS [CHAP. 



phytic characters of these floras are various, 

 but, as M. Costantin observes from his own 

 investigations : 



" We are led to think, so to say, invincibly, 

 that one can only explain the general characters 

 of Arctic plants by adaptation e.g., if all Arctic 

 plants are perennial, it is because they live near 

 the Pole. It is the conditions of life which 

 have created this hereditary character." 3 



As most, if not all, the features characteristic 

 of Alpine plants 2 have been proved by experi- 

 ment to be the direct outcome of a residence in 

 the environmental conditions afforded by an 

 Alpine climate, we are quite justified in regard- 

 ing the latter as being their direct cause. 3 



Numerous experiments were made by MM. 

 Bonnier and Flahault and others, upon the 

 effects on lowland plants when grown at high 

 altitudes and latitudes, and vice versa. Not only 

 do they become dwarfs like native species, but 

 the internal anatomy changes, and becomes 

 similar to the structure of normal Alpine plants. 



That the peculiar characteristics of Alpine 

 plants are hereditary, is a fact familiar to any 

 one who has seen a well-made "rockery," as 

 in the Kew Gardens ; the characteristic feature 

 of all such is the abundance of " Alpine plants " 



1 " Les Vegetaux et les Milieux cosmiques," p. 85 (1898). 



2 I have enumerated them with descriptions, etc., in my " Origin 

 of Plant Structures," pp. 93ff. 



* Op. cit., pp. 112ff. Refs. in note, p. 113. 



