Page:The Zoologist, 1st series, vol 4 (1846).djvu/192

1358 and quite sapless. The insect, though somewhat local was in no scarcity. It was found in splits and chinks, and under the bark where loose ; parties of six or seven, nestling together in a torpid state. They were quite recent, having it is probable lately issued from the lofty beeches still growing on the spot ; — having been induced to choose their present situation, for the sake of shelter, till the genial sunshine should invite them forth anew. They appear to differ considerably in their habits from the bark beetles. The bark under which they lurked was always detached, was entirely destitute of vitality and nutriment ; and presented none of those graphic touches which indicate the route of a destroyer, and by which, as it were, it records its own ravages. Their true residence is the interior of the tree. Almost all the prostrate trees, — huge logs some feet in diameter, are drilled with holes, of the size of those in "worm-eaten" furniture. A few of the insects were seen at the entrance of these, and some had gone into them, as if to reoccupy the deserted passages ; but as all the holes were of remote formation, and showed no tokens of having been recently tenanted ; I was brought to the conclu- sion, that whatever they were with respect to a former generation, they were not the nurseries of the numerous brood at present in their vicinity ; but, like the bark and open fissures, were merely resorted to, as a covert from the night's inclemencies : I could see nothing in the living-trees to sanction this opinion ; no traces of the insects' presence were any where observable in them ; but as the roots of the branches are the favourite seat of insect attack, I consider that if they could have been examined, they would have furnished the requisite evidence. A solitary instance, however, presented itself, in the beeches at Axwell Park wall ; where a branch having been cut oif, an in- sect had settled on the festering limb, and pierced it to the core. The depth of the holes was various, some very slight, others above two inches ; but the measurement be- ing made from without is not conclusive. The timber was injured and blackened for a nail's breadth round the sides of the hole. I found another good example of that adaptative instinct, so wonderful, as coming from creatures so minute, and so remote to our conceptions from the confines of intelligence ; in the plan which some of the in- sects had taken to accomplish their purpose of gaining admission into the tree, with the least possible expenditure of labour. Some idler had carved pretty deeply in the smooth bark the figure of a star. This had been observed by the insects to be a favor- able opening ; and accordingly, the centre, the tip of each ray, with only one exception, and in several places the central line of the rays, were perforated as by a diminutive auger. If the tree were still fresh when this took place, no doubt the exudation of sap might also act as an incentive to this apparently fanciful, but really wise procedure. The holes were also more frequent in those places where the bark had earliest given way, being injured by the rain that frequently lodges in the clefts of large trees. T. domesticum is a pretty little creature; disposed to activity; totters rather than runs, with its tiny, pale antennae carried in a curve ; is very susceptible of warmth ; and readily takes to flight, being provided with ample wings that well enable it to spread its colonies abroad. Judging from appearances, it is somewhat diffused in this neigh- bourhood, as, somewhat later two specimens were taken in the Ravensworth woods, some miles from the first locality ; one in a beech, and the other in a detached branch of oak ; and I have noticed in the rotting willows, mountain ashes, and other timber, several indications of the prevalence of this, or some allied timber-borer, in previous stages of their decay. Of the economy of T. dispar the other British species, an inte- resting and original account is given in Köller's 'Treatise on Injurious Insects,' trans-