44- RAVAGES OF TIMBER-EATING INSECTS 



upon it; and when, from the combination of various causes, 

 (such, for instance, as the weakness of vegetation in a particu- 

 lar air or soil, inattention to the evil at the proper time for ef- 

 fectually checking it, &c.,) the number of insects which attack 

 trees becomes increased beyond its due limit, we must either 

 apply the axe without scruple to the seat of the disease, or make 

 up our minds to submit to the utter destruction of our planta- 

 tions. 



Almost all timber-eating insects are comprised in three or- 

 ders : viz. Coleoptera, or beetles ; Lepidoptera, or moths, but- 

 terflies, &c., and HymenopterO) or bees, wasps, &c. All these, in 

 their youngest state, after leaving the egg, are worms or larvae, 

 and it is while they are in this stage of their life that they commit 

 the direct injury to the trees, either by gnawing off the bark, 

 or by devouring the wood. The communication of the disease 

 to other trees is periodical ; for when the worms or larvae 

 just mentioned arrive at their perfect or winged state be- 

 come butterflies, or beetles, or wasps, &c., the mischief di- 

 rectly committed by them is comparatively trifling, and gene- 

 rally results, in fact, not so much from their voracity, as from 

 their attempts to extricate themselves, and to arrive at the 

 external air ; or from their endeavours to commit their eggs 

 to a proper nidus, or situation, and surrounding materials, pro- 

 per for the vivification and support of the larvae to be hatched 

 from them. But as the insects are now winged, and are 

 capable of depositing myriads of eggs, the germs of as many 

 devouring larvae, the disease is thus dispersed throughout 

 the neighbourhood of the tree originally infected. 



From this general view of the subject, let us proceed to 

 notice some of the ravages which insects have committed upon 

 timber-trees. 



The Pine forests of Germany have at various times sus- 

 tained enormous injury from the attacks of a small Beetle, 

 belonging to the genus Bostrichus, and named by naturalists 

 the Bostrichus Typographies (Fab.) or Printer Bostrichus, on 

 account of a fancied resemblance between the paths which it 

 erodes in the trees, and rows of letters. This insect, in its 

 preparatory or larva state, feeds upon the soft inner bark only 

 of the trees ; but it attacks this important part in such vast 

 numbers, no fewer than eighty thousand larvae being some- 

 times found in a single tree, that it is very far more noxious 

 than any of those insects which bore into the wood itself; 

 and such is its tenacity of life, that though the bark be bat- 

 tered, and the tree plunged into water, or exposed to a freez- 

 ing temperature by being laid upon the ice or the snow, it 

 remains alive and unhurt. The leaves of the trees infested 



