1 68 NOTES OF A NATURALIST. 



will arise for each species that has become common, 

 or, in other words, that other organisms, whether 

 animals or plants, will acquire the means of maintain- 

 ing their own existence at the expense of the new- 

 comer. The wild artichoke is doubtless perfectly 

 adapted to the climate of the warmer and drier parts 

 of the Mediterranean region, and is there rather widely- 

 spread ; but it is nowhere very common, even in places 

 where the ground is not much occupied by other 

 species. We do not know all the agencies that prevent 

 it from spreading farther, but we do not doubt that 

 it is held in check by its appropriate enemies. In 

 South America it would appear that these, or some 

 of them, are absent, and the plant has spread far and 

 wide. If some common bird should take to devouring 

 the seeds, or some other effectual check should arise, 

 the area would very speedily be reduced. 



The train stopped for breakfast at the Rancagua 

 station, a few miles from the town of that name. 

 Along with very fair food at the restaurant, cheaper 

 delicacies were offered by itinerant hawkers, including 

 various sweet cakes of suspicious appearance and 

 baskets of red berries of the petuno tree. At the next 

 station, called Gualtro, about fifty miles from Santiago, 

 we left the train, and, after the usual long delay, con- 

 tinued our journey in a lumbering coach set upon 

 very high wheels. This seems to be the general 

 fashion for carriages in South America, arising from 

 the fact that the smaller streams, which swell fast 

 after rain, are usually unprovided with bridges. 



Incautious travellers in South America may easily 

 be misled by the frequent use of the same name for 



