Larval control project of vector mosquitoes of Japanese encephalitis was carried out by Kyoto City Municipal, starting from surveys of breeding place of Culex tritaeniorhynchus in 1965. Several formulations of granule percolating effective ingredient gradually into water were prepared by some chemical companies, and were evaluated by field and laboratory tests. Granules of fenthion and EPN, which were expected to have continuous larvicidal effect, were applied for larval control by aircraft on rice fields in Kyoto City area from 1967 to 1977. Result of the field evaluation showed effective control against mosquito breeding in the rice fields during 3 to 4 weeks after the application. The factors decreasing vector mosquito population since 1969,when the aerial applications were practiced on the rice fields all over Kyoto City, are scrutinized in reference to the use of herbicides.

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Taxonomy, life history, nest architecture, and nesting habits of Vespa simillima Smith are given. It is one of the most common vespines in Japan and a nuisance pest in residential and urban areas. The species consists of two subspecies, V. s. simillima Smith and V. s. xanthoptera Cameron. In Hokkaido, northern Japan, V. s. simillima colonies last for ca. 4.5 months, i. e., from late May to early October, and mature nests have mean values of 1,821 cells, 6.6 combs and 315 adults. Colony size was considerably smaller than in xanthoptera (southern subspecies), probably because of the short colonial duration in the subspecies simillima. Preferred nest sites differed between the subspecies as well as among habitats. Structural nests were very frequent in urban areas : ca. 50% of a total of 600 nests destroyed in Otaru, Hokkaido, between 1974 and 1980 were built in wall voids of buildings (subsp. simillima), and ca. 70% of 150 nests destroyed in Kyoto, southwestern Honshu in 1978 were in attics (subsp. xanthoptera). In Otaru, ca. 70% of the people injured by the hornet were stung by wasps nesting in wall voids of buildings. Control techniques are given with examples adopted by the Otaru Public Health Centre.

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A Taiwanese Blattella species, rather commonly met with on the ground surface of the lowland, was treated as "Phyllodromia humbertiana Saussure" by Karny (1915) and Shiraki (1931). In recent years Princis (1950a, 1950b) found that they are entirely different from real humbertiana known from Ceylon and India. In his Catalogue (1969) Princis gave its substitute name karnyi (nom. nov.) without any description. Since the only specific diagnosis given by Karny (1915,p. 99) is very poor and inadequate I am giving here a redescription comparing it with Indian humbertiana. I believe accompanying figures will suffice diagnostic characters of both the species.

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d-Tetramethrin is a compound consisting of two parts of d-cis- and eight parts of d-trans-chrysanthemate isomers of tetramethrin. A study was made to evaluate the insecticidal activity of d-tetramethrin in comparison with that of several already known pyrethroids against housefly, mosquito and cockroach under several methods of application. d-Tetramethrin showed about twice as strong killing activity as that of tetramethrin against adult housefly, mosquito and cockroach in the topical application, whereas the killing activity was similar to that of d-allethrin and natural pyrethrins. The knockdown activity of d-tetramethrin was observed to be superior to that of tetramethrin, d-allethrin and natural pyrethrins. The flushing-out activity of d-tetramethrin against cockroach was found to be the best among the tested compounds. d-Tetramethrin is therefore a synthetic pyrethroid characterized by rapid knockdown and flushing-out activities. The applicability of the compound can be widened by adding to it a synergist and/or a killing agent such as d-phenothrin.

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Emulsifiable temephos was applied to two small streams from 1ppm to 20ppm stepwise and drifting macrobenthos were trapped with a net 10m below the application point. Number of species of drifting macrobenthos increased with the sequential application of gradually increasing concentration of temephos, whereas number of drifting individuals of each species showed respective peak at certain concentration of temephos. Simulium larvae were among susceptible species together with four other species, Baetis sp., Isoperla sp., Dolophilodes sp. and Anisogammarus sp. Other approximately 20 species began to drift with 5ppm but 10ppm was necessary to flush out most individuals.

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A new species Typhlodromus (Anthoseius) shibai is described from aging woody tanks of "miso" factories in Ehime Prefecture, Shikoku. T. (A.) takahashii Ehara is a junior synonym of T. (Neoseiulus) bambusae Ehara.

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Tabanus yaeyamaensis, a new species, was described based on the materials from Ishigaki and Yonakuni Islands, Ryukyu. This species is closely allied to T. rufidens (Bigot) in appearance, but can be easily separated from it by having entirely blackish antennae and smoky wings.

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To determine the susceptibility of the wild roof rat, Rattus rattus to warfarin, a no-choice feeding test with 0.025% warfarin bait was carried out using roof rats collected from seven buildings of Tokyo in 1978 and 1979,where the rat population could not be controlled with this bait. All colonies from the buildings showed lower susceptibility than our susceptible laboratory colony. For example, 15 to 25% of the rats of two colonies survived for 90 days. It was suggested that the resistance to warfarin might have developed in some rat populations in Tokyo.

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In this paper I report on infestations of the hothouse millipede Oxidus gracilis about which I was consulted. The infestations followed the pattern of urban sprawl in the suburbs of Tokyo. Infestations reported in the past 6 years (1975-1980) are shown as black circles in Fig. 1. These are located peripherally to the infestations reported in the years previous to this period (black triangles). Reports of infestations of centipedes (Scolopendra) in the Osaka suburbs showed a similar centrifugal pattern.

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Warfarin and scilliroside were administered orally to the wild roof rat, Rattus rattus, captured in Tokunoshima Island where the control with rodenticides was considered to have been scarcely done. Ten days' administration of warfarin resulted in LD50 of 35mg/kg and single administration of scilliroside resulted in that of 1.2mg/kg, suggesting the susceptible level to these chemicals of this species in Japan. On the other hand, the roof rats captured at several buildings in Tokyo where it has been difficult to control the species with these chemicals, were allowed to feed 0.025% warfarin powdered bait. One of the rats captured at Shinjuku survived for more than 70 days, suggesting that resistance to this rodenticide has developed in the urban area.

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