Abstract
Present paper deals with the records of the fall webworm, Hyphantria cunea, which appeared in the mulberry field at Koganei, west side of Tokyo, in 1958.
1. The fall webworm has two generations in a year in the field and three ones in the room.
2. Starting from the fifth instar, 127 species of plants were tested whether the leaves of them are fed upon by the fall webworm or not. It was found that the fall webworm larvae feed and develop on 42 species, feed but scarecely finish the larval stage on 30 species, and no or slight feeding on other 55. But in the seventh instar, the larvae feed and develop even on cabbage and sweet potato, on which the development is not seen in the fifth instar.
3. The feeding and the development of the fall webworm do not suggest any correlation with systematic position of plants.
