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mountainous districts of Syria. Tiie occidental contains 

 Canada, the United States, Japan, and China. 



This simple view is sufficient to prove that these divisions 

 are very arbitrary. Many of these countries may have, and 

 in fact have, an identical mean temperature : they cannot, 

 however, be considered as possessing the same climate. But 

 independently of these divisions being of comparatively little 

 use to science, since of some places where the temperature is 

 the same, the animals are different, it is impossible, in the 

 present state of our knowledge, to obtain a solid basis for 

 these divisions of climate. The different elevations of the 

 soil above the level of the sea, its mineralogical composition, 

 the varying quantity of its waters, the changes produced on 

 temperature by the extent, height, and direction of the moun- 

 tains, by the magnitude of forests, and even by the influence 

 of neighbouring climates, occasion uncertainty and confusion 

 in our calculations from the difficulty of appreciating the 

 just effect of such causes, either singly or combined. 



M. Latreille would consider climates under another point 

 of view. This is presented by the genera of arachnida and 

 insects which are exclusively proper to certain determined 

 spaces of the surface of the earth. With the imperfection 

 of catalogues, especially in foreign species, it would be diffi- 

 cult to pursue a different plan. Even the entomology of 

 Europe cannot be considered in this point of view as any 

 thing but very remote from perfection. Many, even scien- 

 tific travellers, may be reproached with having neglected 

 the precise indication of the places where they have found 

 the objects with which cabinets of natural history are en- 

 riched. Their inattention, therefore, to the physical and 

 mineralogical characters of the soil in such situations, can 

 excite little surprise : yet such particulars constitute an es- 

 sential part of the history of animals. The licmi, papilio 

 cleopatra^ some lamice, &c. are only found in calcareous 



