Page:The Zoologist, 3rd series, vol 2 (1878).djvu/368

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344
THE ZOOLOGIST

informs us regarding the ravages of two species of beetles that out of three hundred and fifty trees cut upon the estate, one hundred and twenty were dead, or at least gone in the top, owing, he believes, entirely to their ravages. Can anyone in the same way produce appreciable proofs of damage which can be laid correctly to the charge of the Capercaillie, and if so to what extent? What amount of good can be traced to the destruction of insect life by the Capercaillie ? How long does the insect-feeding age of the birds continue? What insects or larvæ, and what amount of them, do the young Capercaillies consume ? Do the old birds never eat insects, beetles, or larva? of any kind? To solve these and other minor questions the crops and gizzards of both young and old birds should be examined with the critical eye of the entomologist, and exact statistics of the contents of each crop and gizzard noted down under each separate specimen, with the dates and localities, and when possible the probable or exact age of the bird. Birds from a day or two old up to the adult stage should be critically examined during the summer and early autumn months. Special attention should be paid to the presence of larvae in the mouths, throats, and crops of young birds as soon alter death as possible, or even of living young birds. Positive identification of the insects is of the highest importance, and the number of individuals should be carefully counted. Where personal ento- mological examination is practicable of the crops and gizzards of newly killed birds, such should be taken advantage of. Where personal entomo- logical examination cannot be instituted, the crops and gizzards of each bird should be kept separately in close muslin bags, with parchment labels attached, and the whole dropped into alchohol : an ordinary wide-mouthed pickle-jar would probably hold three or four crops and gizzards, or more if the birds be young. The jars can then be forwarded to entomologists for identification of the contents. Dr. Buchanan White, of Perth, has promised assistance in the identification of insects. Mr. Robert Collet, of Christiania, who takes a great interest in the matter, will also devote some share of attention to it in Norway. Mr. Maloch, Perth, has promised to preserve any crops and gizzards that come in his way. Capt. Colquhoun, of Clathick, has offered assistance; and Mr, Maclellan, Superintendent of Parks, Glasgow, has also taken an interest in the subject. There is still a considerable degree of scepticism evinced by many as to the utility of such enquiries ; unthinkingly they often pooh ! pooh ! the efforts of naturalists to get at the more minute truths, which do not always appear on the surface, but upon which not uncommonly the whole question at issue hinges. Investigations often begin in ignorance, and from a spirit of enquiry develop truths of considerable interest. Men are not all Argus-eyed naturalists, who can detect at once, at all times, and under all circumstances, the reasons for everything. If such were indeed the case Natural History would be robbed of half its charms."