DESTRUCTIVE INSECTS. 23 



stones, and he found it as great a waste of time to look for it 

 upon a smooth limestone as to turn up a fragment of basaltic 

 rock (whitstone), in search of a geodephagous (i) insect. "So 

 far," says Mr. Wailes, "as my observations, whether confined to 

 single stones, or extended over a whole district, go, any place 

 having limestone, particularly the magnesian, for its subjacent 

 stratum, will aiford abundance of the geodephaga as well as most 

 other coleoptera, whilst they will be found very thinly scattered 

 over a basaltic region." (2) 



(1) Geodephagous. The geodephaga form a coleopterous subdivision containing 

 two families, the cicindelidee and the carabidse. Of the former there are between 

 fifty and sixty species known in the United States and Canada. They prey on insects. 

 The carabidJB are very numerous, predaceous, feeding upon insects and also upon 

 vegetables. They are generally found under stones and rubbish. 



(2) Quoted in Enc. Britt. 8th Ed. 



