266 THE ENTOMOLOGICAL WONDERS OP THE TKOPICS 



also, while the whole of Europe and Siberia hardly possess more 

 than 250 diurnal Lepidoptera, or butterflies, the explored parts 

 of Brazil, which are very inferior in extent, have already fur- 

 nished the naturalist with no less than 600 species, and no doubt 

 contain many more. 



The carrion-feeding beetles, however, form a remarkable 

 exception to this general rule, as they are most numerous, 

 both absolutely and relatively, in the temperate regions of the 

 northern hemisphere — most likely from the extreme rapidity of 

 decomposition in the torrid zone not allowing the developement 

 of their larvae to keep pace with the progress of putrefaction. 

 Thus the families of the Carabi and Hydrocanthari have only 

 591 and 65 species in South America and Mexico, while they 

 respectively number 1,090 and 156 in Europe and Southern 

 Russia. 



Another peculiarity of beetle-life in the equatorial zone is^ 

 that in tropical America most Carabi live on the trees, while in 

 our country they all, with rare exceptions, dwell upon the ground — 

 a circumstance probably due to the legions of ants which there 

 take possession of the soil, and so effectually perform the duties 

 of scavengers as to leave but little for others. 



In the countries which, from the never-failing abundance^ 

 of food, and constant warmth, are 

 most favourable to the multiplica- 

 tion of insects, these creatures may 

 naturally be expected to attain the 

 greatest size. 



Thus the European rhinoceros 

 beetle {Oryctes nasicornis), though 

 an inch and a quarter long, is far 

 surpassed by the Megasominac of 

 torrid America. 



The colossal Hercules beetle {M, 

 hercules), which is sometimes seen 

 in great numbers on the Mammee 

 tree (Mammcea Americana), attains 



Hercules Beetle. ■, ■, n r* • • i 



a length of five or even six inches, 

 and is distinguished, like the other species of the genus, by 

 the singular horn-shaped processes rising from the head and 

 tliornx, which give it a very grotesque and even formidable 



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