Forest entomology . Fig. 121.—Pityogenes biden-tatus. (From FishersForest Protection.) COLEOPTERA—SCOLYTIDtE. 125 As this beetle has proved a veritable pest on the Continent, andalso occasionally in this country, it would be well to guard against itsravages. Perhaps the best preventive would be to remove or burnall comparatively young fresh branches which would come in prox-imity with any fairly large coniferous trees planted out, either inparks or villas, for immediate effect. Genus Trypodendron. The beetles of this genus are entirely different in their workingsfrom the sections hitherto cons
Forest entomology . Fig. 121.—Pityogenes biden-tatus. (From FishersForest Protection.) COLEOPTERA—SCOLYTIDtE. 125 As this beetle has proved a veritable pest on the Continent, andalso occasionally in this country, it would be well to guard against itsravages. Perhaps the best preventive would be to remove or burnall comparatively young fresh branches which would come in prox-imity with any fairly large coniferous trees planted out, either inparks or villas, for immediate effect. Genus Trypodendron. The beetles of this genus are entirely different in their workingsfrom the sections hitherto considered. The Trypodendron mother-beetle bores directly into the stem of the tree for about J to |- inchdeep, directly towards the centre or pith, but when this depth is. 122.—Block of wood shown in perspective to illustrate the workings of the genusTrypodendron. (After Eckstein, and copied from Niisslin.) reached she bends slightly round and then bores in a somewhatcurved direction, parallel to the circumference of the tree, and alwayspreferring the sap-wood. After she has taken the bend referred toshe makes a sort of recess or basket, alternately right and left, of themain gallery, and places a single egg in each recess. In due timethe eggs hatch out and make short galleries at right angles to theparent gallery. Each gallery points upwards or downwards. Asregards space, each gallery alternates, and thus Ave get laddergalleries formed. When fully developed, the offspring creep outat the entrance made by the mother-beetle. The accompanying figure, fig. 122, taken from Niisslin, is a sort ofperspective representation of an infested block, and gives a very goodidea of how the insect bores into the stem. The generic characters are : Eyes divided i
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