412 



cocoon, (4) pupa, (5) young beetle in the cocoon, (6) winged adult 

 injuring shoots, (7) wintering adult, and (8) ovipositing adult. Qf 

 these stages, in only 1, 2, and 8 are control measures practicable. '.'.' 

 3Iyelophilus piniperda, L., was on the wing from 23rd March to 

 7th April ; oviposition began on 26th March and continued till 11th 

 May ; the first larvae were observed on 26th April and about a month 

 later all the larvae were already in the bark, the first pupae appearing 

 on 25th May and the first beetles on 13th June. The adult M. pini- 

 perda remains for a longer time in the galleries than that of M. minora 

 but eventually emerges and attacks the pine shoots. There is some 

 evidence that these beetles, as in the case of M. wiwor,.hib,efji^te.find 

 oyiposit a second time. •.,,,,, 



' Ips sexdentatus, Born.,'wap on the wing; from 25th April to Isf^May, 

 when oviposition began ; the first larvae were observed on 19th May, 

 tlie last ones on 7th June ; pupae were found between 8th June and 

 the niiddle of July. Young beetles underneath the bark occurred from 

 the middle of June to the middle of August. The old beetles do not 

 remain in the galleries, but emerge and most probably oviposit a second 

 time. The beetles oithe second generation began to bore themselves in 

 on 12th June., -^.-ndi c^^)J^,n; o '- jt:.,i^ :-:,,u\ '},■:: Ai ]o ii;.' ; n'.nni:. :';•: 

 .bi'-'i.iv. j;'..'.&& oi.'iiv/ ,boov/ oil.j n'l Woy, oiJi oJni ^(^liiv')id;i'>v ilnira yi9v/ ,j^noi 



Rapper (0.). Ucnena monacM:^« JitcHOM mypHan'fc.» [Forestry 

 ^j,. Journal], Petrograd, xlv, no. 10, 1915, pp. 1420-1459. 



^•^ This is the first instalment of a review of the biology and' control- of 

 lAjmantria (Ocneria) mmiaclia. In Eussia this insect first attracted 

 kotice in the fifties of the last century, when it destroyed many hundreds, 

 of square miles of forests ; it has been reported from 30 governments 

 of European Russia, the northern limit being 58° N. Lat. and the 

 Southern one, 54° N. Lat. ; it has also been recorded from Irkutsk in 

 Siberia. The females oviposit in August underneath the bark of trees, 

 where the eggs remain over the winter ; their vitality is very great 

 and according to some authors they are able to withstand intense frost 

 and even a long submersion in water ; Dr. Metzger obtained cater- 

 pillars from eggs subjected to a treatment with 4 per cent. carboHc acid,, 

 in order to destroy possible bacteria of flacherie. In autumn the eggs 

 are more sensitive to climatic conditions, and dry, hot weather in 

 August and September may delay their development. The young 

 caterpillars are fully formed in four weeks and winter inside the egg, 

 emerging in spring at a temperature of about 57° F. Hatching continues 

 for about a month. There are four or five moults ; the reason for this 

 discrepancy is not known, but it may have some relation to sex, for the 

 individuals that moult only four times give rise to a larger proportion of 

 females. The newly hatched caterpillars are mainly found along the 

 borders of forests, where the buds are earher ; they exhibit great 

 vitality at this stage and in a dry atmosphere can withstand a tem- 

 perature of 19° F., or even 10° F., for several hours. They are poly- 

 phagous, feeding on fir, pine, oak, ash, etc. They exhibit a preference 

 for trees growing in low-lying situations, which may account for their 

 tendency to spread to such places. According to Ebermaier, there 

 exists a direct relation between the amount of evaporation and the ash 

 content of leaves, and the same trees may contain a different amount 

 of ash according to whether they grow in high or low places. Although 



