Forest entomology . markings arevery characteristic, as in ; but later on the larvalmarkings are very much inter-mingled, as in fig. 103, whichis a photograph from a por-tion of bark, and shows theintermingling of larval gal-leries from several adjacentbroods. At first the larval galleriesare very fine and thread-like,but as the grubs enlarge thegalleries widen, and pupationtakes place at the end of the larval gallery. It should be noted thatboth larval and mother galleries are always made in the bark, andnever in the wood, though the frass always lies on the wood after theremoval of th
Forest entomology . markings arevery characteristic, as in ; but later on the larvalmarkings are very much inter-mingled, as in fig. 103, whichis a photograph from a por-tion of bark, and shows theintermingling of larval gal-leries from several adjacentbroods. At first the larval galleriesare very fine and thread-like,but as the grubs enlarge thegalleries widen, and pupationtakes place at the end of the larval gallery. It should be noted thatboth larval and mother galleries are always made in the bark, andnever in the wood, though the frass always lies on the wood after theremoval of the bark. Thus the beetle in question is a baric beetle. The beetles escape from the pupal chamber by making direct exit-holes, and thus the numerous flight-holes in the bark indicate thata new generation has escaped. The beetles arising from the first-deposited eggs hatch out in aboutthree to five weeks, generally towards the end of June, and theseearly hatched beetles, on quitting the galleries, deposit eggs in the. 103. — Portion of bark of Scots pine, showing twomother-galleries and larval workings. 110 FOREST ENTOMOLOGY. bark of felled trees, preferring those trees which have been felled inlate spring or early summer. But meanwhile the stem-mother haskept on depositing eggs, and beetles hatch out from the parent burrowthroughout the season, but more especially in the autumn. Thus theperfect beetles arising from the second brood, together with the lateswarmers just referred to from the original burrow, quit the barkpractically simultaneously, and bore into the young leading shoots ofthe Scots pine branches, entering the pith, and thus damaging theshoots, so much so that they fall to the ground, and the beetles there-fore may be found inside the pith of those shoots which so literallystrew the ground of pine woods in autumn. Some specimens leave the shoots to hibernate in the bark, andothers remain in the shoots over winter, to comeout again in the following spring. The cont
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