On (he Geographical Distribution of Insects. 171 



It thus appears that the creo-saprophagous species dimmish 

 from the Poles to the Equator in an infinitely more rapid 

 manner than the creo-thalerophagous, and nearly in the same 

 ratio in both Continents. The rarity of these insects has been 

 long' since remarked in inter-tropical America, and a similar 

 observation was made at a still earlier period, by Dr Horsfield, 

 in relation to Java. This author alleges as the cause, that 

 the ants and termites have taken full possession of the gTound ; 

 but why should these insects have destroyed the Necrophaga 

 rather than the Carabidae, which likewise live on the surface 

 of the ground, and of which a considerable number are found 

 in Java .'' The scarcity in question may be much more plau- 

 sibly ascribed to the too rapid decomposition of carcasses and 

 other animal substances, as has been stated above. 



It is more difficult to form a similar estimate in regard to 

 the phytophagous Coleoptera, because their thalerophagous 

 and saprophagous species are mingled in the same families, 

 and there are many with the nature of whose food we are im- 

 perfectly acquainted. Besides, the Saprophaga comprehend 

 no small portion of Xylophagi and Brachelytra, which are so 

 much neglected by collectors on account of their small size, 

 tliat Ave are scarcely acquainted with any inhabiting countries 

 out of Europe. No calculation of this kind, for the eight re- 

 gions established above, would therefore lead to any satisfac- 

 tory issue. But the attempt may be made for the different 

 countries of Europe, of which the entomology is best known, 

 and tlie following is found to be the result : — 



From this it may be presumed that, contrary to what takes 

 place with the creo-saprophagous Coleoptera, the phyto-sapro- 

 phagous species go on increasing from the Poles to the h^quator ; 

 it is remarked, indeed, that the Coprui)liaga and Longicox'nes 



