155 



injured by the bamboo sboot borer, Polydesina vulgaris, Butl., the 

 damage done amounting to from 30 per cent, to 80 or 90 

 per cent. The variety of bamboo most Uable to injury, " Kuchiku," 

 is unfortunately also the most useful, the other species, except 

 "" Medake," being free from the pest. The larvae infest the bamboo 

 shoot when it is from one to two feet long, and from one to 

 ten individuals or more may be found in a single shoot. When 

 attacked, the shoots become yellowish in colour and wither, barely 

 reaching a length of 4 or 5 feet. The first attack usually occurs from 

 the middle of June to the beginning of July. The fully grown larva 

 leaves the shoot and pupates under the ground. The adult moth 

 appears at the end of July and beginning of August, and in the middle 

 of the latter month lays round milky- white eggs in rows on the bamboo 

 leaf. The winter is passed in this stage, and there is only one brood 

 in a year. There has been much difference of opinion amongst 

 entomologists as regards the life-history of this pest, since the eggs 

 hatch in May at a time when the ordinary bamboo shoots have not 

 yet appeared, and the larva afterwards found within the shoot is 

 always well developed and of a length of 10-15 mm. The present 

 author states that the earliest larval stages are spent in the slender 

 early shoots of various species of bamboo in the forest, and that later 

 migration occurs to the shoots of the ordinary variety, which are entered 

 by boring into the apex. This habit suggests a possible remedial 

 measure, in that the removal of the early slender shoots from the 

 bamboo forest may check this pest effectually. Experiments in this 

 direction are being conducted by the author. 



MuRAMATSu (S.). Oni juyahoshi no Keikwa. [The Life-History of 



Epilachna rdponica, Lew.] — Konchu Sekai [Insect World], Gifu, 

 xxiii, no. 1, 21st January 1919, pp. 17-20. 



The CoccineUid, Epilachna niponiai. Lew., has three broods a year. 

 It passes the winter in the adult stage and becomes active at the 

 beginning of May, ovipositing at the end of the month. The adults 

 of the second generation appear in the middle of June and those of 

 the third from the end of July to the beginning of August. The 

 beetles that will eventually hibernate are found in September. The 

 adult hides beneath the foliage by the day and becomes active in the 

 early morning and evening. This beetle attacks potatoes, egg-plant, 

 tomatoes, etc.,, throughout Korea. A mixture of soap solution and 

 insect powder is the most effective remedy against it. 



Takahashi (S.). Daima no Gaichu to Daima-Iengyu ni tsukite. [Notes 

 on Insects injurious to Hemp and on Thyestes gebleri, Fald.] — 

 Konchu Sekai [Insect World], Gifu, xxiii, no. 1, 21st January 1919, 

 pp. 20-24, 2 figs. 



The author records 13 species of insects injurious to hemp, viz., 

 Thyestes gebleri, Fald., Haltica flavicornis, Baly, Barathra brassicae, L., 

 Pyrausta nubilalis, Hb., Hepialus excrescens, Butl., an undetermined 

 Tortricid, Acronycta consanguis, Butl., Rhinonchus pericarpius, L., 

 Mordellistena cannabisi. Mots., TetUgonia ferruginea, F., var. apicalis. 

 Walk., Geisha distinctissima, Walk., Bicania japonica., Melioh., and 

 Aphis sp. Of these the first three are the most destructive. 



(C562) b2 



