COLEOPTEHA. CARABIDiE. 



Firr. 3. 



75 



pleasantly variegated than in the majority of the family. Other pecu- 

 liarities have already been pointed out. 



This sub-family, as at present constituted, is perhaps the most in- 

 congruous of all the sub-families of the Carabidte, the term Trunca- 

 tipennes applied to it by Latreille by no means indicating a constant 

 character, as many of the species have the elytra rounded at the tips. 

 The tarsi indeed are generally alike in both sexes, or if dilated in the 

 males, the dilatation is of a different character from that of the other 

 sub-families. In may, indeed, be rather regarded as a convenient 

 receptacle for such groups as have not the bipartite and palmated 

 structure of the Scaritides, the simple tibiae of the Carabides, the 

 dilated male tarsi of the Harpalides and its subdivisions, or the minute 

 conical terminal joint of the maxillary palpi of the Bembidiides. The 

 tarsal claws are often denticulated (^Jig. 3. 8. claws of Lebia) ; but this 

 structure is found elsewhere in the family. 



The typical species of this sub-family are endowed with a means of 

 defence of the most singular description, from whence they have 

 derived the name of Bombardier-beetles, and which was first men- 

 tioned by Ilolander in the Transactions of the Academy of Stockholm 

 for 1750. When the insect is attacked by other and larger insects, 

 or placed in a situation of danger, it suddenly emits from the anus a 

 fluid of so highly volatile a nature that, immediately upon coming into 

 contact with the atmospheric air, it becomes a bluish vapour of a very 

 pungent scent, accompanied with considerable explosion, whereby the 

 insect is enabled to effect its escape. This it is enabled to repeat 

 seven, eight, or even a dozen times. It is stated by an anonymous 

 author (^Ent. Mag. iii. 377.), that on immersing a specimen of Br. 

 Gra-'cus in boiling water, it let off one of its explosions, and the water 



