A phytophagous ladybeetle, Henosepilachna yasutomii was found to be widely occurring on a deciduous tree, Pterostyrax hispida (Styracaceae), in the mountainous regions of Chichibu (Saitama Prefecture), Okutama (Tokyo Metropolis) and adjacency (Gunma and Yamanashi Prefectures). A herbaceous plant, Scopolia japonica (Solanaceae) was also utilized as a subsidiary host plant, in case available. The pest type H. yasutomii beetles ("Western Tokyo Form") feeding on potato and eggplant in Hinode, Tokyo, did not accept P. hispida leaf at all in the laboratory, indicating that the pest population is rather different in feeding habit from the wild populations.

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Morphological variation and life cycle of Aphis neospiraeae Takahashi were investigated at Tomakomai, Hokkaido, northern Japan. Large-sized apterous and alate viviparous females (1.7mm or more in length) showed well developed dorsal bands or a large dorsal patch on the abdomen and siphunculi longer than cauda. Small-sized apterous and alate viviparous females (less than 1.5mm in length), however, showed small dorsal median sclerites or no sclerites on the abdomen and siphunculi equal to or shorter than cauda. The life cycle was found to be monoecious and holocyclic on Spiraea salicifolia. The fundatrix appeared from the end of May, and oviparous female and male from the end of September and the beginning of October, respectively. In this paper these three morphs are described for the first time.

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New bionomic information of the Japanese bumblebee, Bombus hypocrita hypocrita Perez, is given, basing on the examination of 8 nests collected in Tochigi and Nagano Pref., central Japan between 1979 and 2003: 1) Underground nest sites were prevalent, but surface or aboveground nests were also observed. 2) Wax envelope was frequently present in mature nests. 3) Connection of cocoons was loose and peripheral cocoons tended to detach from the cluster of cocoons. This brought about the irregular arrangement of batches. 4) Colony size was not so large as compared with that of B. ignitus and B. diversus, the number of cocoons/colony rarely exceeded 500. 5) Output of new queens was also relatively small and the average number of queen cocoons/mature colony was 64. 6. 6) Only one adult female of the pupal parasitoid, Mutilla europaea mikado Cameron, was found in one of 8 nests. All features are shared with those of the lowland consubgener, B. ignitus, except that colony size and output of new queens are smaller in B. h. hypocrita than in B. ignitus.

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