WEEDS 207 



and so on, you will get a poorer competition than if 

 all were open. 



Dominance is much the same in the tribes of men 

 as among plants and animals. We understand the 

 dominance of the European better when we re- 

 collect how race after race has fought for mastery in 

 Europe. We understand the dominance of English- 

 men over remote savages better when we reflect upon 

 the ancient wars within these islands, the " scuffling of 

 kites and crows," when tribes of all kinds strove 

 together with life or death as the issue. Let the 

 survivors of such a competitive examination as that be 

 brought face to face with some long-isolated Polynesian 

 people, and can it be doubted for a moment which 

 will prevail ? Races of men, races of animals, races 

 of plants, religious faiths, modes of civilisation, all 

 originate in the northern continents, and spread out in 

 successive waves. But there is no return-current. 

 The plants and animals of the southern continents 

 can no more return to Europe or Asia than the 

 Basques and Finns can recover Central Europe. The 

 Palaearctic Region, and in a less degree North America, 

 have been the officina gentium of which Jornandes 

 spoke, the laboratory in which new tribes are fashioned, 

 the starting-point of waves of migration which at 

 length reach to the remotest corners of the earth. 



Our common European weeds are the very strongest 

 in competition of all plants. They have come out 

 first in the contest for place. Most of them produce 

 plenty of light seeds, which are easily dispersed by 

 the wind. Most of them are hardy and able to endure 

 extremes of temperature. Most of them are self- 



