MEANS OF DEFENCE OF INSECTS. 



201 



grainy fluid without smoke. 1 Another species (B. displosof) 

 makes explosions similar to those of B. crepitans : when irri- 

 tated it can give ten or twelve good discharges ; but after- 

 wards, instead of smoke, it emits a yellow or brown fluid. By 

 bending the joints of its abdomen it can direct its smoke to 

 any particular point. M. Leon Dufour observes that this 

 smoke has a strong and pungent odour, which has a striking 

 analogy with that exhaled by the nitric acid. It is caustic, 

 reddening white paper, and producing on the skin the sensa- 

 tion of burning, and forming red spots, which pass into brown, 

 and though washed remain several days. 2 This burning sen- 

 sation, M. Lacordaire informs us, when arising from the dis- 

 charges of the large exotic species, is so painful, that he has 

 often been obliged to let those which he had taken escape. 

 The same power of emitting explosions, as a means of defence, 

 is found also in some other coleopterous species, as in those of 

 the genus Paussus, according to M. Payen, who had an op- 

 portunity of studying their habits in the isles of Sunda and 

 the Moluccas 3 ; in those of Cerapterus according to Mr. Mac- 

 Leay 4 ; and in those of Ozcena in a slight degree, according 

 to M. Lacordaire. 



Another expedient to which insects have recourse, to rid 

 themselves of their enemies, is the emission of disagreeable 

 fluids. These some discharge from the mouth ; others from 

 the anus : others again from the joints of the limbs and seg- 

 ments of the body ; and a few from appropriate organs. 



You have doubtless often observed a black beetle crossing 

 pathways with a slow pace, which feeds upon the different 

 species of bedstraw ( Galium), called by some the bloody-nose 

 beetle (Timarclia tenebricosa). This insect, when taken, 

 usually ejects from its mouth a clear drop or two of red fluid, 

 which will stain paper of an orange colour. The carrion- 

 beetles (Silpha and Necrophorus), as also the larger Carabi, 

 defile us, if handled roughly, with brown fetid saliva. Mr. 

 Sheppard having taken one of the latter ( C. violaceus), applied 

 it in joke to his son's face, and was surprised to hear him im- 



1 Trans. Ent. Soc. Lond. ii. proc. vii. 



2 Ann. du Mus. xviii. 70. 3 Lacordaire, Introd. a VEntom. ii. 56. i 

 4 Westwood, Mod. Classif. of Ins. i. 151. 



