THE EXPLOSIVE LIQUID. 37 



naked hand, leaving a mark winch remained for a considerable 

 time. Upon observing the whitish vapour with which the ex- 

 plosions were accompanied, the negro exclaimed in his broken 

 English, with evident surprise, 'Ah! Massa, they make smoke." 



The explosive fluid is soluble both in water and alcohol, and 

 after repeated explosions deposits a sort of dust on the elytra. 

 The interior of the reservoir is coated with the same dusty 

 deposit. 



The name Brachinidae is derived from a Greek word signify- 

 ing " short," and was given to these Beetles because most, though 

 not all, of them have their bodies shortened and almost squared 

 behind, as if they had been cut off abruptly with a knife or 

 chisel. 



Fig. 12.— Pterosopluis complanatus. Brachinus Sinensis. 



(Dark blue with yellow marks. ) (Brown with green gloss.) 



In the accompanying illustration the left-hand figure repre- 

 sents the Ptcrosophus comjilanatus of India. It is a very pretty 

 creature, and in its general outline and the arrangement of its 

 colours really exhibits a curious similitude to the well-known 

 Asparagus Beetle of this country. The ground colour of the 

 elytra is dark, shining, violet-blue, and the patches upon them 

 are yellow, as is the thorax. The shortened form of the elytra 

 is shown very plainly in this insect. 



On the right hand of the same illustration is one of the largest 

 of the true Brachini ; namely, the Chinese Bombardier Beetle 

 (Brachinus Sinensis). This insect really looks quite a giant 

 among its kinsfolk ; and if it be able to eject a corresponding 

 quantity of the volatile fluid, it must be rather a formidable 

 antagonist to any insect foe. 



As is the case with many other Beetles, the colouring of this 

 insect is rather variable. It may, however, be described as 

 follows. The general hue is brown, slightly glossed, however, 



