Proteins of the haemolymph and fat body of Henosepilachna adults were analysed by polyacrylamide gel electrophoresis and the changes in the protein components were compared during the prediapause period in relation to the diapause induction. Some of the female-specific proteins like vitellogenin were identified but these proteins were not the major ones in the ovary of this species. There were no diapause-specific proteins, while the quantity of most of the protein components in the haemolymph and fat body increased with the lapse of the prediapause period. A protein in the haemolymph disappeared at the time corresponding to the loss of photoperiodic sensitivity when the fat body was fully developed for the diapause. Chromoproteins, which were colourless immediately after adult emergence, became yellowish with a slight decrease in their relative electrophoretic mobilities, after the onset of adult feeding.

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In order to evaluate the scaring effect of a mannequin on the Roufous Turtle Dove, Streptopelia orientalis, food sites were set up in a flight cage and a mannequin was placed at these sites. The period during which captive doves visited the food sites for feeding was measured to obtain an index of the scaring effect. When a mannequin was placed at one of two food sites, the doves did not visit the site with the mannequin. However, when the food was restricted to the site with the mannequin, doves gradually visited this site and the feeding time increased with the passage of time. Scaring effect of a mannequin whose body and face were covered with cloth was somehow stronger than that of a mannequin with an uncovered face, although the difference between the two conditions was not sizeable. These results suggest that the response of doves to a human model is not as strong as that to a novel visual stimulus, and that it changes depending on the amount of food which the birds can take.

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Flight activity of insects was studied using truck trap from April to December in the northern part of Tochigi prefecture in Japan. In the samples, 304 thrips belonging to 31 species were collected. The most abundant species consisted of Ecacanthothrips inarmatus KUROSAWA and Thrips flavus SCHRANK. A few males were present in 9 out of 31 species. A marked peak in the numbers of individuals and species was observed in September.

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Two clones originally collected from tobacco (=tobacco form) and three clones from radish or Chinese cabbage (=non-tobacco form) of Myzus persicae (SULZER) were reared on tobacco and potato in the laboratory (15L-9D, 20°C) to evaluate their adaptation to tobacco. On potato there were no significant differences between the tobacco and non-tobacco forms in the developmental period (8-10 days) or in the survival rate in the larval stage (96-100%). On tobacco, however, remarkable differences were observed between the two forms: the developmental period was slightly longer than that on potato in the tobacco form (9-14 days), and much longer in the non-tobacco form (10-20 days); the survival rate in the larval stage was 98% in the former, and only 10% in the latter. On tobacco, alate virginoparae of the tobacco form lived for 15-29 days and produced 19-63 larvae per female, although those of the non-tobacco form lived for a shorter period of time (3-8 days) and produced fewer larvae (0-17). These results suggest that the susceptible forms to tobacco are eliminated from tobacco within a few generations even if alate forms settle on the plant and only the resistant forms survive there. Some characters of the aphid, which may possibly contribute to the resistance to tobacco, are discussed.

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The stage of overwintering diapause is the egg in Antheraea yamamai and the pupa in A. pernyi. Development from the embryo to the adult was investigated in the F₁ hybrids between A. yamamai _??_ and A. pernyi _??_ (YP) and those between A. pernyi _??_ and A. yamamai _??_ (PY) under the conditions of 12L-12D (25°C) (SD: short day) and 15L-9D (25°C) (LD: long day) in order to analyse the genetic system controling the diapause. All of the normal embryos hatched within 18 days from oviposition, and no diapausing embryos were observed. No differences between YP and PY or between SD and LD were detected in the embryonic development. Days from hatching to the start of spinning numbered 40 in YP _??_, 31 in YP _??_, 33 in PY _??_ and 30 in PY _??_ on the average, and these was hardly any difference between the SD and LD conditions. Ratios of diapausing pupae, which refer to the pupae that did not become adults within 100 days from the start of spinning, were 100% in YP-SD _??_, 91% in YP-SD _??_, 100% in YP-LD _??_, 63% in YP-LD _??_, 15% in PY-SD _??_, 95% in PY-SD _??_, 95% in PY-LD _??_ and 97% in PY-SD _??_. On the basis of these results, the genetic control of the life cycle was discussed.

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An experimental aimed at the suppress in of the male population of the melon fly, Dacus cucurbitae, was conducted in the central part of Okinawa Island in 1982-1983. For the suppression of the male flies, 0.83g of a lure-toxicant mixture which consisted of 85% cue-lure, 5.0-5.5% naled and 10.0-9.5% solvent was infiltrated into a piece of cotton rope (0.7cm in diameter, 5.0cm long). Aerial application from helicopter and hand application on the ground were adopted for dispensing the cotton ropes containing the lure-toxicant. The application density was 40 per hectare and the applications were repeated monthly four times from August to November, 1982. The relative number of flies caught in the traps in the treated area decreased by about 1/6 compared with the untreated area after the first application and 1/100 after the final one. The effect persisted for 5 months throughout the winter.

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Larval susceptibility in solitary and gregarious phases of Pseudaletia separata to Nomuraea rileyi was examined under laboratory conditions. The larvae reared in isolation were more susceptible and died in a shorter period of time than those reared in crowds when the final-instar larvae were inoculated percutaneously with N. rileyi. The difference of susceptibility was also observed when gregarious larvae were reared in isolation after the inoculation. The pale larvae which were produced under crowded rearing conditions were more susceptible than the black larvae when N. rileyi was inoculated percutaneously. However, no differences in the susceptibility and time of death were observed between the solitary larvae and the gregarious larvae when N. rileyi was inoculated subcutaneously.

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Four species of acarid mites which had not been previously recorded in Japan were observed on various plants mainly in Hokkaido, northern Japan, and their morphological features were described. The damage caused to the crops was also briefly reported. Tyrophagus similis VOLGIN, 1949, commonly occurred on spinach in Hokkaido, and was also found to be injurious to melon, cucumber, pumpkin and maize in many parts of the island. Tyrophagus perniciosus ZACHVATKIN, 1941, was injurious to spinach, melon and pumpkin, but its distribution was limited to several areas of Hokkaido. Tyrophagus neiswanderi JOHNSTON et BRUCE, 1965, was collected mainly from plants grown in greenhouses in Hokkaido, Honshu and Kyushu, but injury was reported only on cucumber in Ibaraki Prefecture, Honshu. Mycetoglyphus fungivorus OUDEMANS, 1932, was collected only from spinach and seemed to be restricted to eastern Hokkaido. Its hypopus has not yet been found in Japan. The first record of the genus Mycetoglyphus OUDEMANS, 1932, in Japan is reported in this paper.

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As the parent plants withered in autumn, adult females moved to the rosette. Throughout the winter, all stages of T. desertorum were observed on the rosette, and adult females survived winter without entering diapause. Laboratory experiments also confirmed the non-diapausing nature of this population.

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