Common Beetles of our Countryside 



Fig. 4). both larger and smaller than this. The 

 size of P. vitreus is about 10 mm. long ; entirely 

 shining black with a thorax broader than long, 

 rounded at the sides and contracted behind. But it 

 is most easily recognised by the linear series of deep 

 impressions or pits which run down each elytron ; 

 these vary in number from three to six, but are always 

 very district, and the only other British Pterostichus 

 which bears similar markings is P. oblongo punctatus, 

 which is rather more brassy in colour and is never found 

 near the summits of mountains. 



Besides P. vitreus there is another Pterostichus which 

 we may find as high up as there are stones scattered to 

 turn over. This is very similar in colour and slightly 

 larger in size, but there are no deep impressed punctures 

 on the elytra, and the shape of the thorax is slightly 

 different, being not quite so much contracted behind 

 as it is in P. vitreus. This is called Pterostichus cethiops 

 (the black Pterostichus) ; Fig. 20, Plate VI. The only 

 species we could confuse with it might be P. madidus 

 (see Plate A, Fig. 2). and that insect which does 

 sometimes occur high up on the mountains, although 

 much the same shape, is nearly 5 mm. longer, rather 

 more shining black, and the legs, especially of the 

 upland form, often red. 



These are all the mountain Pterostichi we are 

 likely to discover, but there is another character- 

 istically Alpine beetle we ought to find under some 

 stone up here. It is the sole representative we 

 have in this country of its genus, Miscodera, and its 



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