80 THE WORLD OF LIFE 



and publish the results of their combined work on a uniform 

 plan, and in a cheap form, the total expense for all the 

 nations of Europe combined would be a mere trifle. Here 

 is a great opportunity for some of our millionaires to carry 

 out this important scientific exploration before these glorious 

 forests are recklessly diminished or destroyed — a work which 

 would be sure to lead to the discovery of great numbers 

 of plants of utility or beauty, and would besides form a 

 basis of knowledge from which it would be possible to 

 approach the various great governments urging the establish- 

 ment, as a permanent possession for humanity, of an adequate 

 number of such botanical, or rather biological, " reserves " 

 as I have here suggested in every part of the world. 



Before leaving the very interesting problems suggested 

 by the floras of " small areas," I will point out that in the 

 tropics, in warm temperate and in cool temperate zones 

 alike, the evidence goes to show that mountain floras are 

 not so rich in species as those of the plains. I have already 

 shown that it is the case in our own islands, in Switzerland 

 and in South Europe. The table of extra-European small 

 areas (p. 36) shows that the great Japanese mountain, Fuji- 

 yama, with a larger area and an altitude of over 12,000 feet, 

 has a smaller number of species than Mt. Nikko, with a 

 smaller area and an altitude of only 8000 feet, both 

 mountains being cultivated to the same height (800 feet), 

 and both being equally well explored. And now, coming 

 to the tropics, we find in Java two areas of the same extent 

 and fully explored by the same botanist, one on a grand 

 mountain slope from 4500 to 9500 feet, and celebrated for 

 its rich flora, the other at the sea-level, and the latter is 

 decidedly the richest. Yet we find Gardner, in his Travels 

 in Brazil, taking the very opposite of this for granted. He 

 says, at the end of his work : " No good reason has yet been 

 suggested to account for the greater number of species which 

 exist on a given space on a mountain than on a plain." 

 The answer seems to be that there is no such general fact 

 to be explained. There may often, no doubt, be more plants 

 on some mountains than on the adjacent plains, especially 

 on open plains where social plants abound. On mountains 



