Forest entomology . Fig. 247.—Cone of silverfir (Abies pectinata)partially eaten by larvceof Dioryctria abietella. LEPIDOPTERA. 259 The moth (fig. 248) may be described as follows : Fore wings longand narrow, glossy dark-grey, with several wavy black transverselines. Easal and first lines preceded by a white fascia ; first line verydistinct on costa; secondline angulated and borderedon its outer margin with awhite line; an indistinctshaded grey line betweenit and the hind margin ; apale central spot on disc ofwing. Hind wings concol-orous. Length 22 to 25 mm. This species belongs to thefamily
Forest entomology . Fig. 247.—Cone of silverfir (Abies pectinata)partially eaten by larvceof Dioryctria abietella. LEPIDOPTERA. 259 The moth (fig. 248) may be described as follows : Fore wings longand narrow, glossy dark-grey, with several wavy black transverselines. Easal and first lines preceded by a white fascia ; first line verydistinct on costa; secondline angulated and borderedon its outer margin with awhite line; an indistinctshaded grey line betweenit and the hind margin ; apale central spot on disc ofwing. Hind wings concol-orous. Length 22 to 25 mm. This species belongs to thefamily of Crambites, and typical moths of the same may be seen fly-ing, or rather leaping on the grass fields, in a summer evening 248.—Dioryctria abietella (full size). (Drawn byP. J. Brown.) Family The moths of this family are comparatively small, and some natur-alists have proposed for systematic considerations, as regards externalanatomy, to merge it with the Tineidae. This suggestion, however,has not met with much support, and from an arboreal point of viewthe two families should be considered as quite distinct. The nameTortricidae refers to the general habit the larvae of those moths possessof rolling up leaves, or twisting and distorting shoots and buds. Themode of rolling leaves by small larvae has been much discussed, andis probably due to definite operations of the larvae, together withassistance derived from silk threads spun by themselves. These silkthreads are rolled round the leaves, and they harden and contractfrom exposure to the air. After the leaf is thus bound by the tinythread, the roll is still further perfected by the growth of the vege-table organism accruing from the interfe
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