COLEOPTEEA OK BEETLES. 149 



be roughly identified ]jy their hard convex elytra, long thin legs 



and antennEe, and their extremely active habits. The majority 



are carnivorous, and do immense good 



by devouring noxious insects, molluscs, 



and animal matter. The mouth is 



armed with a large scissor-sliaped pair 



of mandibles, with which they cause pio. ee.— Ground - beetle 



great havoc amongst insect hfe. Some ^dumiT "°""""^' """ 

 species have wings, others have none. 



The larvae of Carabidaj are elongated and flat, slightly tleshy, 

 with a hard chitinous head and fir.st segment : there are three 

 pairs of legs on the first three segments, and two horn-like ap- 

 pendages on the dorsum of the tail segment, sometimes an 

 elongated process below : like the adult, the larvas have power- 

 ful scissor-like jaws. These larvae are also carnivorous, and 

 have a similar diet to the adult. The two most commonly 

 met with are the Garden Ground -beetle (Carahus violaceus) 

 (fig. 66) and C. neriioralia. The former is a large purple beetle, 

 often seen actively running about fields and gardens ; the latter 

 is golden-bronze in colour. Both are predaceous, and so are the 

 majority of this famUy ; but some have developed decidedly 

 injurious vegetarian habits, attacking corn and strawberries to a 

 disastrous extent. 



The Corn Ground-beetle (Zahrus r/ibhus) injures the roots of 

 corn in the larval state ; the adult destroys the barley in the ear, 

 and lives during the day in tunnels in the ground. They are 

 black - coloured beetles, about an inch in length, with broad 

 heads and strong biting jaws. Another species, Steropus mandi- 

 dm, somewhat smaller, has been recorded as devouring mangel- 

 wurzel, attacking the young roots, often gnawing them off at 

 the level of the ground. This beetle is also carnivorous. The 

 same species and two others — Harpalus ruficornvi and CaJafJnis 

 cisteloides — have in recent years been working among straw- 

 berries, numerous inquiries during the past two years reaching 

 the author. H. ruficornis, the most abundant, is about two^ 



