164 THE GEOGRAPHY OF PLANTS, 



In Chili and Patagonia, an elegant and tall 

 tree of the pine tribe (Araucaria imbricata) 

 forms extensive forests, and produces cones the 

 size of a child's head, which supply the natives 

 with a great part of their food. It is said that 

 the fruit of one large tree will maintain eighteen 

 persons for a year. A very remarkable cir- 

 cumstance attends the burning down of such 

 primeval forests, a circumstance which not 

 infrequently takes place in these and othei 

 parts of America on both sides of the equa- 

 tor. The same kind of trees as those which 

 formed the original forest never re-appear 7 

 but some other species, which had previously 

 been strange to the spot, spring up instead of 

 them. Thus, in Patagonia, if one of these 

 pine forests be burned, the ground on which it 

 grew is soon covered with an impenetrable 

 brushwood of other plants. In Chili, the vio- 

 lently stinging, but beautiful climbing loasa, 

 appears first in these burned places, bushes grow 

 afterwards, and then comes a tree grass, eighteen 

 feet high, of which the Indians make their nets. 

 In Pennsylvania, when the ancient forests are 

 burned, they are succeeded by a thick underwood 

 of rhododendrons. In each of these instances, 

 the primitive forests had no undergrowth, and in 

 each, also, the kind of plant which appears as a 

 successor is constant, according to the character 

 of the forest destroyed, and the country where 

 situate. A somewhat similar circumstance 

 occurred in this country after the great fire in 

 London, in 1666 ; a great quantity of Sisym- 



