INSECTS INJUKIOUS TO AGRICULTURE IN JAPAN 19 



layer. Control measures employed when necessary are the collection 

 of egg clusters during the winter and spraying with Sapporo solu- 

 tion or naptha emulsion shortly after the hatching of the eggs. 



Himera pennaricD has the same range of distribution as the above 

 species and feeds upon apple. Okamoto (JJfl) records one brood per 

 year, the adult moths appearing early in May and depositing their 

 eggs upon the bark. The larvae feed until late in August, when they 

 enter the soil and pupate, the winter being passed in the pupal stage 

 in Hokkaido. Breeding studies at various experiment stations in 

 Honshu, however, have given rather different life histories, some 

 indicating hibernation in the egg stage and others in the mature 

 larval or pupal stages. 



The tent caterpillar Malacosoma neuistria testacea (73, 11$) is 

 found throughout all of the main islands of Japan and in Chosen, 

 China, Manchuria, and Siberia as well. Extensive damage is done 

 to many varieties of fruit trees, chiefly apple, pear, plum, and cherry. 

 This species is particularly injurious in Hokkaido and northern 

 Honshu. One brood a year is produced, and hibernation is in the 

 egg stage. The eggs are laid in masses of from 250 to 300 in rings 

 about the twigs. Hatching occurs at the end of April in Hokkaido, 

 and the colony of young larvae builds itself a tent-shaped web at a 

 crotch of the smaller branches. This web has a single entrance and 

 is gradually enlarged. Feeding is done during the day outside the 

 web, and the larvae return to it for the night or during cool periods. 

 When maturity is reached the web is abandoned. 



The combined larval stages cover a period of about 10 weeks, 

 and pupation occurs about July 1, the whitish cocoons being formed 

 within the folded leaf, though an occasional larva may return to the 

 old web for pupation. The duration of the pupal stage is from 30 

 to 36 days, the adults emerging early in August and the females 

 depositing their eggs the latter part of that month. Control meas- 

 ures employed are the collection of egg clusters during the fall and 

 winter, the destruction of the colonies of young larvae in the web 

 during the early spring, and the collection of adult moths at lantern 

 traps. 



Gastropacha quercifolia {117) is common, though not particularly 

 injurious, upon apple, pear, plum, and apricot throughout Japan, 

 and is recorded from Chosen and China also. There are two broods 

 a year, and the winter is passed in the larval stage upon the branches 

 or trunk of the host tree. The overwintering larvae become active 

 in April and feed upon the newly developing foliage. The adults 

 of the first brood appear in June and those of the second the middle 

 of August and in September. The eggs are laid in masses of 400 or 

 more upon the leaves and branches. 



Odonestis pruni (117) occurs upon apple and pear in Japan, 

 Chosen, and China, but is of minor importance. Two broods are 

 produced each year, the adults appearing in June and August, 

 respectively. The life cycle and habits are practically identical with 

 those given for G. quercifolia. 



Of the minor lepidopterous pests of apple and pear the noctuids 

 Acronycta incretata, Pangrapta obsaorata, and Taeniocampa incerta 

 may be mentioned. A. incretata (95) (often listed in literature as 

 tridens Schiff.) is found in Hokkaido, Honshu, Chosen, and China, 



