CHAP. XXXII.] FAILURE OF INSTINCT. 275 



cause us to look with some suspicion on the further exten- 

 sion of that system. It must be remembered too that our 

 commerce is not a purely natural growth. It has been 

 ever fostered by the legislature, and forced to an unnatural 

 luxuriance by the protection of our fleets and armies. The 

 wisdom and the justice of this policy have been already 

 doubted. So soon, therefore, as it is seen that the further 

 extension of our manufactures and commerce would be an 

 evil, the remedy is not far to seek. 



After six weeks' confinement to the house I was at 

 length well, and could resume my daily walks in the 

 forest. I did not, however, find it so productive as when 

 I had first arrived at Dobbo. There was a damp stagna- 

 tion about the paths, and insects were very scarce. In 

 some of my best collecting places I now found a mass of 

 rotting wood, mingled with young shoots, and overgrown 

 with climbers, yet I always managed to add something daily 

 to my extensive collections. I one day met with a curious 

 example of failure of instinct, which, by showing it to be 

 falhble, renders it very doubtful whether it is anything more 

 than hereditary habit, dependent on delicate modifications 

 of sensation. Some sailors cut down a good-sized tree, and, 

 as is always my practice, I visited it daily for some time in 

 search of insects. Among other beetles came swarms of 

 the little cylindrical wood-borers (Platypus, Tesserocerus, 



T 2 



