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New Holland cannot be confounded with those of the ancient 

 world of the same classes. The insects of the United States, 

 though often very nearly approximating to ours, are yet 

 removed from them by some characters. The insects of 

 New Granada and Peru, countries neighbouring to Guiana, 

 and alike equinoxial, yet differ in a great measure from 

 those of the latter, because those regions are separated by 

 the barrier of the Cordilleras. A sim.ilar sudden change is 

 observable in passing from Piedmont into France by the 

 defile of Tende. These rules may admit of some exceptions 

 with regard to aquatic species. On the other hand, we find 

 insects whose habitat is very much extended. The papilio 

 cardui, so common with us, and even in Sweden, is to be 

 found at the Cape of Good Hope, and a species nearly re- 

 lated to it in New Holland. The sphinx nerion and the 

 sphinx celerio are found in France and in the Isle of France, 

 the former seeming to be their northern, and the latter their 

 southern boundary. The dytiscus griseiis, which inhabits 

 the waters of Provence and Piedmont, is no stranger in 

 Bengal. 



'Many genera of insects, and particularly those which feed 

 on vegetables, are spread over a great number of points of 

 the principal divisions of the globe. Some others are exclu- 

 sively peculiar to a certain extent of country, whether in the 

 Old or New World. 



Many species in their native country exclusively affect 

 certain localities, either in low situations, or in those which 

 are elevated, and at an equally constant lieight. Some Alpine 

 butterflies are continually confined to the regions of perpetual 

 snow. In ascending mountains, when we come to a height 

 where the temperature, vegetation and soil are the same as 

 those of a much more northern country, we discover there 

 many species which are peculiar to the latter, and which 

 would be sought for in vain in the plains and vallies which 



