And now a word of justice to these beetles. It might be supposed that, by burrowing into trees, they caused the death of the latter, but this is not really the case. Writing in _The Agricultural Gazette_ of New South Wales for August, 1900, Mr. Froggatt, the Government Entomologist, makes the following statement absolving _Xleborus_: “This curious little beetle (_X. solidus_) is rather plentiful about Sydney, and is frequently sent to us taken out of the trunks of fruit trees, which it is supposed to have killed; but in all cases that have come under my notice it has had nothing to do with the tree dying, but is attracted to the tree as soon as it becomes sick, the bark begins to wither, and the first symptoms of decay set in.” Mr. Froggatt adds: “The instinct that leads these and other wood-boring beetles to a tree as soon as it is sick is something marvellous; in the tropics I have collected many fine, rare species upon the freshly cut tent-poles in our camp, attracted to the wood, but otherwise seldom found in the bush.” This instinct would seem to be a remarkably developed scent, though why a severed branch should smell differently from the tree of which it but a moment before made a part it is not easy to imagine. However, we cannot, without evidence, attribute clairvoyance to beetles, and perhaps it is the cut from which the scent emanates. Another example of an insect which is neither an ant, bee, wasp, nor white ant, but which yet may be said to live a true social life, is the little creature which, under the name of _Psocus venosus_ and as belonging to the order _Carrodentia_, will be familiar to everyone. It is nearly related to the so-called book-lice, but lives in the open air, “being seen,” says Mr. Leland Howard, “upon the trunks of trees, in flocks numbering from twelve to forty or fifty individuals.”[69] These browse together like a herd of miniature cattle on the various lichens that embrace the bark, and these they nibble so closely that wherever they move they leave a bare track behind them. Sometimes one family and sometimes several are included in the herd, all ages and stages being represented, from the wingless but free-moving larvæ to the winged imago form. The latter, however, though they be thus provided, will not readily forsake their young, but the whole of them, when alarmed, first run all together, and then, if the cause of disquietude continue, suddenly scatter as though in panic, and run hither and thither, in all and every direction. When the danger seems over, they close up their ranks again, and go on browsing as before.