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jured in any \\a\- by tire or axe, by drougiit or by exposure of the 

 surface roots to a hot sun from destruction of undergrowth, by 

 defoHation from swarms of caterpillars or from natural decay, 

 it is liable to be attacked by the special kind or kinds of these 

 borers that attect it. 1')}' the outsider the work of the borer is 

 usuall}- noticed after the death of part or the whole of the tree, 

 when the borings beneath the bark and the numerous exit holes 

 of the beetles become ol)vious ; but those who are observant may 

 notice the beetles themselves running rapidly in the sunshine over 

 the trunks and branches of still living trees. At night and on 

 wet days they usually remain hidden in the undergrowth. If held 

 in the hand, they squeak audibly, and some of them have no less 

 than three diti'erent sets of sound-producing apparatus. A few 

 appear to be found in apparently healthy trees and not to partic- 

 ularly injure these, since they produce abundant seed annually 

 in spite of the attack. These beetles are so rarely found in 

 forests that have not been interfered with by man and his 

 animals, that it is quite certain that, in a natural condition of the 

 forest, they are beneficial rather than injurious insects, as they 

 help to remove old and sickly trees and make room for younger 

 growth. Two parasitic was]:»s attack the larvae of these borers, 

 and in some cases cause a great mortality. In the case of one 

 species, of more than one hundred larvae collected, only two 

 produced beetles, all the others yielding i)arasites. One species 

 of the latter is a comparatively recent introduction, the other, 

 though doubtless an accidental importation, has been known for 

 more than thirty years. On Alaui a very remarkable native bird 

 (Pscudoncstor) exists, which is ])cculiar to that island, and is 

 specially formed for securing the larvae and immature beetles 

 of these borers. On many occasions its food was found to con- 

 sist solely of these, and the number destroyed was remarkable. 

 Dther native birds that are allied t(^ the Pscndoncsfor, and which 

 a''e seen in the same trees, feed on other species of borers, but 

 either are not able to obtain tliis kind or else they have no liking 

 for them. It is a matter for surnrise that, exce])ting on M;nii, 

 none of the common naliv bird^ with wood])ecker-like habits 

 should have availed themselves of such a food sui)i)l\-. 



In I'igs. 4 anrl ? are shown two small weevils nnich magnified. 

 since thev do not exceed one-f|uarter of an inch in length or are 

 still smaller. P'ig. 4 is a species of DryoMifhonis. of which there 

 arc manv different kinds, black and reddish in color, small dirty- 

 lookinsr insects, often smeared with t'xcretions ami adherent jiar- 

 ticles of rotten wood. The\' ai'e freiiucntb extremel>' nnnuTons 

 in dead trunks or branches of trees and also in rotten logs hing 

 r)n the .•'■roimil. Manv individuals associate together, and these 

 companies frenuentiv consist of several different sjiecies. None 

 of the species can be considered as at all injurious {o the forests, 

 tliouLdi thev are sometimes suimosed to be so by those who have 

 not studied their habits. On the lowlands one species, which is 

 no doubt an introfluction, docs nnuh damage to boards, if thev 



