. Injurious and useful insects; an introduction to the study of economic entomology. Insects; Beneficial insects; Insect pests. THE GOAT-MOTH 67 the sawdust which falls from their workings, by the holes in the trunk and the sap which oozes from them, by the empty pupa-skins sticking out from the trunk, or, in some cases, by the disagreeable sour odour, rather like that of crude acetic acid, which is given off by the larvae. It is on account of its peculiar smell that the insect has received the name of goat-moth. The full-fed larva makes its way to the surface of the tree-trunk, and there pupa
. Injurious and useful insects; an introduction to the study of economic entomology. Insects; Beneficial insects; Insect pests. THE GOAT-MOTH 67 the sawdust which falls from their workings, by the holes in the trunk and the sap which oozes from them, by the empty pupa-skins sticking out from the trunk, or, in some cases, by the disagreeable sour odour, rather like that of crude acetic acid, which is given off by the larvae. It is on account of its peculiar smell that the insect has received the name of goat-moth. The full-fed larva makes its way to the surface of the tree-trunk, and there pupates about midsummer, within a cocoon of sawdust lightly spun together. The cocoon is placed close to the outlet of the gallery, so as to facilitate the escape of the moth. The pupa is of a reddish brown colour; the- fore part of its body is com- // ^V\! pressed to the shape of a wedge; on each /'/^"""''^^^ of the abdominal segments is a single or / .^^^^i double transverse row of pointed projections, ^\#\. ijwi and the end of the body bears short spines, ^s^ 1 Wl Such roughening of the skin is common in pss^^^l larvae or pupae, which have to travel along ^ narrow spaces. The pupal stage lasts only )""'—«''! two or three weeks. When the time for y,,,,^^...,, , emergence comes the pupa cleaves its cocoon L }}3i by pressing its wedge-shaped body against it, and moves onwards till the wing-sheaths are fe^ completely protruded from the hole. The '' fore part of the pupa-skin then splits into >k^^^^^_. two, and the winged moth becomes free, the empty pupa-skin being left sticking out of the hole. Sometimes the larva pupates under- Fig. so.—Pupa of ground in an earthen cocoon. Ly"onet!"° ' The damage done by the larvae of the goat- moth is often not discovered until the trees are seriously injured. It is easy to draw out, or at least to destroy, the caterpillars by passing a wire into their holes; or a wash of soft soap and pet
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectinsects, bookyear1902
