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fulled asli timber, busily engaged in oviposition. It is about two lines in length, 

 is clothed above with cincrcv^us u.ud lubcous soules, beneath with an ashy pile, 

 antennae fen-uginous, with a lai-ge acuminated fuscous club, legs piceous, tarsi 

 ferruginous ; it is extremely variable in coloiir, being of different hues of 

 black, piceous, ferruginous, or testaceovis, sometimes ochraceous, with the legs 

 and antennje paler ; usually it is ferruginous, with uregidar piceous markings, 

 H. Fraxini appears very decidedly to prefer recently fallen timber to the 

 growing tree ; they will even attack wood that has been cut many months. 

 Early in May the perfect beetles are often to be seen swarming about fresh ash 

 logs ; they arrive on the wing, and jtrefer the warm sunshine of the early 

 morning for their flight ; they must often travel considerable distances. They 

 bore very rapidly, however, into the bark. The female commences the gallery 

 by boring obliquely towards the wood, usually in a slightly upward tliiection, in 

 large timber choosing the deepest part of a crevice of the bark ; in younger 

 wood a knot or other in-egularity determines the preference, so that, unless the 

 frass lies about the aperture, they are difficult to detect. Frass, I may explain, 

 is a term applied to any detritus caused by insects, and especially to the sawdust, 

 &c., made by wood -boring beetles. Usually before the female beetle has quite 

 buried itself in the bark, the male arrives, and is waiting to enter the burrow, 

 if not, the female bores down to the wood, and there awaits his conung ; and I 

 believe I have met with burrows uncompleted because the male insect did not 

 appear. I have satisfied myself that each pair of beetles first meet after the 

 female has commenced the burrow. In a few days the two beetles are to be 

 found rapidly extending the gallery in both directions from the apertm-e of 

 entry, close to the wood and usually slightly in it, and transversely to its fibres. 



I suspect each of the beetles excavates a branch, but I have found no 

 means of observing them at work, as opening the gallery always stops them, and 

 it is possible that the female does the greater part of the excavation, as I have 

 always found her further from the aperture of entry when both were in the same 

 branch of the burrow ; the male is also oftener at its opening, and eggs are laid 

 along each as rapidly as it is formed, not unfrequently the branches of the 

 gallery are of very unequal length, so much so that sometimes there is practically 

 only one— possibly both beetles work together. Undoubtedly the greater part 

 of the excavated material is eaten ; in captivity the beetles will live a long 

 time with fresh ash bark, without it they soon die. Most insects on their 

 escape from the pupal state contain their eggs ready to be laid and requiring only 

 fertilization, but in these, as in many of the more active Coleoptera, the eggs 

 are developed after attaining the perfect state. In the case of Hylesinits Fraxini 

 the female is often bulkier when the burrow is half completed than on entering 

 it, and the eggs laid by a single paii- must often exceed in aggregate mass the 

 original bulk of the female beetle. The domestic habits and family relations 

 of these beetles deserve further attention. The following suggestive experiment 

 was made : A burrow was partially opened, some few eggs had been laid, each 



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