Abstract
1. It was observed that early type soybean varieties (which are suited for seeding in spring) had been seriously damaged by some insects for these few years. 2. Investigations were made on the kinds of the insects, the extent of the damage by each insect, and the relations between the damage and the soybean varieties or the date of planting. 3. Both Nezara antennata SCOTT and Riptortus clavatus THUNB. damaged soybeans ; especially in the case of the latter, the damage was serious. 4. The damage of soybean seeds by the insects varied with the stage of development of seeds. In the earlier stage of maturing the damage was more serious than in the later stage. 5. The early type soybean varieties were more seriously damaged by the insects than the late type ones (suited for summer seeding). In the above two type soybeans, the earlier the date of flowering, the more serious was the damage. 6. The earlier the date of planting, the more serious the damage, in the both type soy-beans. The later the date of planting, the better the yield of early type soybeans, which was the reverse to the normal case in which greater yield is produced by early seeding.
