DISTRIBUTION OF THE PETALOCERA. 4? 



The Petalocera, however, occupy so important a place in 

 the ceconomy of nature, that we may easily perceive it to be 

 impossible to assert in what latitude they altogether cease 

 to exist. But though it may not thus be easy to prescribe 

 limits of latitude to any of the Petalocerous families, it is 

 otherwise with respect to the longitude ; for we find that the 

 Glaphyrida have never as yet been found but in the old 

 world, nor the Rutelida but in the new. As to the remaining 

 eight families, they appear to have been confined within no 

 limits of longitude, nor indeed of habitable latitude, though 

 we shall see that some families are more plentiful in parti- 

 cular climates than others. Thus the Aphodiidce seem to be 

 most numerous in rather high latitudes, the Geotrupida in 

 temperate climates, and the Scarabaeidce in tropical. The 

 Trogidce and Melolonthidce appear to be scattered rather 

 equably over the globe, which may in some degree arise 

 from their partiality to a particular soil. The Dynastida, 

 Cetoniida, Anoplognathida, and Rutelidte, though found 

 in the tempei^ate zones, are all most numerous in the 

 warmer climates ; but the two first families recede much 

 farther from the equator than the two last. The Glaphy- 

 rida, however, of all the Petalocerous families appear to 

 be the most confined in their range of climate. 



In some cases also the geography of the Petalocera is 

 affected by local circumstances ; for the Dynastidcs which 

 are common in America and on the European Continent, 

 have never yet been discovered in England, although the 

 Oryctes nasicornis inhabits even the high latitudes of 

 Sweden. If however the truth of the preceding remarks 

 be allowed, such incidents are readily accounted for, since 

 a Petalocerous insect of a. tropical family may readily be 



