33O THE NATURAL HISTORY 



philus aquaticus, Elaphrus cupreus, Elaphrus riparius 

 and Bembiditnnflavipes, we find more frequently near 

 water, particularly on the dried mud at the edges of 

 ponds. Zabrus gibbus occurs in our cornfields, Abax 

 striola everywhere, and of the pretty little Brachinus 

 crepitans we have met with several specimens under 

 stones, &c., in the hedgerows on Hucksholt and Castle 

 Farms. We had often read of the Bombardier Beetle, 

 long before we had an opportunity of identifying the 

 insect, but the first specimen we captured fired off 

 such a volley of " stern chasers " when we put it into 

 a wide-mouthed phial and gently stimulated it with a 

 straw, that notwithstanding all we had learnt from* 

 books on the subject, we were quite taken by surprise. 

 This then, we thought, is the prudent individual that 

 never travels without his pocket revolver, and makes 

 such excellent practice with it when called upon to 

 defend himself ! The ordinary occasions on which 

 this artillery is played off are when the Bombardier, 

 which is less than half-an-inch in length, is closely 

 pursued by other and larger insects of prey ; if it 

 finds itself about to be overtaken by its assailant, it 

 astonishes the latter w'ith such a loud explosion, accom- 

 panied by a wreath of blue smoke and a very pungent 

 odour resembling that of nitric acid, that the pursuit 

 is .checked for a few seconds, the chase is soon re- 

 newed, however, to be again interrupted by a well- 

 aimed shot, and so on a dozen or twenty times in 

 succession if necessary. So caustic is this volatile 

 ammunition, which is expelled from two reservoirs 

 near the posterior extremity of the body, that if its 

 effect on the sensitive antennae of insects resembles 

 the burning sensation it produces on the skin of the 

 Entomologist, the frequent escape of the Brachinus 

 from its enemies need not excite our surprise. 



The Pcelobius Hermanni, Colymbetes maculatus, 

 Acilius sulcatus, Dyticus marginatus, Dyticus circum- 

 flexus, and Gyrinus natator are among our com- 



