Forest entomology . wig (see fig. 168), about theend of June. During the earlysummer months the galls are ofa close woody structure, buttowards the autumn they aremore or less hollow, and containa comparatively large amount ofdirty black frass. Several larvaeare found within one gall. Itmay happen on inspection thateach larva is enclosed within acocoon. This condition I foundon January 5, 1900, but it mustnot be inferred that the larvaeare fully fed, as the cocoon maybe either for protection or shelter. The larvae commence making their pupal cocoons about the middleof April, for by April 28, 1
Forest entomology . wig (see fig. 168), about theend of June. During the earlysummer months the galls are ofa close woody structure, buttowards the autumn they aremore or less hollow, and containa comparatively large amount ofdirty black frass. Several larvaeare found within one gall. Itmay happen on inspection thateach larva is enclosed within acocoon. This condition I foundon January 5, 1900, but it mustnot be inferred that the larvaeare fully fed, as the cocoon maybe either for protection or shelter. The larvae commence making their pupal cocoons about the middleof April, for by April 28, 1900, they were all in the pupal stage. The larvae when full fed are about 8 to 9 mm. long, of a uniformslaty-whitish colour, with darkish head. The six true legs are welldeveloped, and there are six pairs of thoracic legs. The flies hatch out from the 9th to the 15th of May. The lengthof the body is about 2 lines. Expanse of wings 6 lines ; antennae9-jointed. Body wholly black ; legs brown, with darkish Fig. 168.—Galls o/Euura pentandraj on shootso/Salix pentandrre. Pontania salicis (Christ.)Nematus bclliis, Zad. The galls are formed on the leaves of Salix caprece (goat willow).It is generally most abundant on hilly districts. In some seasons it 182 FOREST ENTOMOLOGY.
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