Common Beetles of our Countryside 



The whole base and the centre of the front margin are 

 deeply punctured, the elytra a rather long oval some- 

 what faintly striated. The genus Patrobus comes next 

 to Trechus in our lists (see Plate II., Fig. i), but 

 our three species are all much larger than any British 

 Trechus, and resemble each other very much, all being 

 of a dark pitchy or brown-black colour without markings. 

 Of the other two, one is exclusively a Scots and the other 

 quite a mountain species. This genus, quite northern 

 and western as it is in its range, is a good example of 

 what has been termed the " Keltic " element in our insect 

 fauna, that it to say, it represents a number of species 

 which probably were native to Great Britain when these 

 Islands formed part of a great extension of North- 

 Western Europe into the North Atlantic Ocean, possibly 

 before the Glacial Age, certainly before the great influx 

 from the Continent across what is now the North 

 Sea on the cessation of glacial conditions, of the vast 

 majority of our fauna which now have their centres of 

 greatest abundance in the East and South of this Island. 

 Possibly, once commonly and widely spread over the 

 whole country , these "Keltic " species have been forced, 

 partly by the changed conditions of climate, partly by 

 the competition of new arrivals from the South-East, 

 into those remote fastnesses of North- Western England, 

 Wales, Scotland and Ireland, where we find them 

 to-day. 



We may meet on these moors with several such beetles 

 of a more ancient lineage than those we find on the 

 Downs, and still more were we to ascend the mountain 



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