66 



feed extensively at the roots. In Hokkaido S. salebrosa at times 

 causes considerable damage. There is one generation per year, and 

 the winter is passed by the adults in the old pupation cells in the soil, 

 from which they emerge in May and June. Rotation of crops is 

 recommended as the best means of control. In Chosen a related 

 species (jS erica similis) is quite abundant and at times causes damage 

 by the feeding of the adults upon the foliage of young plants in the 

 early spring. 



Maladera (Aserica) orientalis (3£) is a serious pest of sugar beet 

 in Hokkaido. There is one generation each year, and the winter 

 is passed in the adult stage in the pupation cell in the soil, the final 

 transformation taking place in late August and early September. 

 The beetles feed upon the young foliage, largely during the evening. 

 According to Yamada (§05) the species is also a serious pest in Man- 

 churia, and crop rotation is recommended as the most practicable 

 means of control. 



The chrysomelid Monoxia puncticollis, one of the well-known 

 sugar-beet pests of the western part of the United States, is recorded 

 as occurring in Japan and Chosen, but no information is available 

 regarding its habit or the extent of damage inflicted. 



The flea beetle Chaetocnema ckalceola is recorded as a pest in 

 Hokkaido, but not much is known regarding its habits. Control 

 measures advocated are the same as for the garden springtail, which 

 is discussed later. 



The sugar-beet tortoise beetles Cassidm nebulosa and C. nigroguttata 

 (95) are minor pests of sugar beet in Hokkaido and northern Hon- 

 shu. There is a single generation each year in that section and two 

 farther south. The adults hibernate in sheltered places, emerging 

 early in the spring. The females deposit their eggs upon the under- 

 sides of the leaves. The grubs feed upon the foliage, and the pupae 

 are formed on the leaves. 



Another important pest in Chosen is the curculionid Scepticus 

 inmlaris (1), which feeds upon the foliage of many other crops 

 in addition to sugar beets. There is one brood a year, and hibernation 

 is in the larval stage, the adults appearing in late April and May. 

 The larvae live in the soil and do little damage, most of the injury 

 being due to the feeding of the adults upon the foliage of the young 

 plants. The control method suggested is the growing of other favor- 

 ite food plants along the borders of the fields. 



The curculionid Gneorrhinus globatus (W5)\s a serious pest in 

 southern Manchuria and is recorded also from Chosen and Taiwan. 

 The adults, which are present in the field from March to May, 

 feed on the leaves and buds of the young plants and often kill them. 



The meloid beetle Epicauta megalocephala (7, 205) is found com- 

 monly feeding upon the beet foliage in Chosen and southern Man- 

 churia and is recorded also from Japan. The adults appear in 

 May and feed throughout the summer upon the foliage. There is 

 one generation annually. Control measures recommended are cul- 

 tivation after harvesting to kill the larvae in the soil and the collec- 

 tion of adults during the early mornings, when they can be knocked 

 from the plants into receptacles and killed. In Taiwan E. hirticornis 

 (85) is recorded as attacking sugar beet, potato, and various other 

 crops. The adults appear in May, and the eggs are laid in June 



