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for information relative to the economy of Hylobius Abietis, and the plans best 

 adapted to arrest the ravages of this beetle : — 



" London, Sept. 18, 1860. 



"My dear Sir, — Your favour, accompanied by specimens of Hylobius Abietis and 

 twigs of larch from which they had gnawn the bark, reached me in due course on the 

 3vd. The interesting remarks on the ravages of the beetle, and the specimens, were 

 communicated to the Society at its meeting on the same evening, and an account will 

 appear in the ' Proceedings.' 



" Having ransacked such foreign works as I possess which treat on insects inju- 

 rious to foresters, for information respecting the Hylobius, the following memoranda 

 will perhaps prove not altogether unacceptable. 



" This beetle appears to attack indiscrimately all the species of fir cultivated in 

 Germany, preferring however, according to Ratzeburg, Pinus sylvalicus and P. abies. 

 In countries where firs are not grown this insect seems to be unknown. 



" It is the perfect insect alone which is directly injurious. It gnaws the young 

 shoots, causing them to wither. The extremities of a tree thus attacked (the most 

 vigorous and healthy trees are invariably selected by the beetle) several years in suc- 

 cession, sickness and death inevitably ensue; in dry seasons especially, the mischief 

 this beetle occasions in fir woods where it abounds, is almost incredible. 



" The perfect beetles emerge from May to October, and copulation takes place 

 from the period first named to about the end of June, but is rarely witnessed later in 

 the year: the beetles which make their appearance after this lime hybernate, and do 

 not copulate until the ensuing spring. The female deposits her eggs, and the larvae 

 subsist, either in the stems of sickly or dead, standing or felled trees, or in the stumps 

 and roots of those which have been felled remaining in the ground, and are therefore 

 scarcely to be considered as directly injurious. Hence it will be obvious that by grub- 

 bing up all stumps, and keeping the plantations cleared of all sickly and dead trees, 

 an important step will be made towards reducing the numbers of the beetles. All 

 timber should be barked as soon after it is felled as practicable, as the females lay 

 their eggs in the bark only. All dead branches likewise should be lopped ofi" close to 

 the stem. 



" Ratzeburg mentions several plans adopted in Germany for entrapping the 

 beetles : of these the most successful appear to be — 



" 1. Pits and trenches with perpendicular sides, dug at frequent intervals round 

 the plantations and along the sides of the paths or road-ways, into which the beetles 

 fall or fly, and from which, being unable to escape, they are to be taken and destroyed. 



" 2. Bunches of young fir boughs laid about the plantations or in the pits. These 

 are to be shaken daily over cloths, and the beetles collected and destroyed. As soon 

 as the boughs commence to dry they prove unattractive, and must be replaced by 

 fresh ones. Ratzeburg informs us that 2500 beetles have been taken daily from 100 

 of these bunches or bundles. 



" 3. Strips of fresh fir bark strewn about the plantations with the inner surface 

 downwards allure the beetles in great numbers ; on lifting these the insects are found 

 congregated upon and beneath them. 



" I remain, &c., 



" Edward W. Janson, 

 " To W. Elliott, Esq." 



