Geographical distribution of domestic cockroaches around human dwellings was studied using sticky traps in three seasons: spring, summer and fall, in the whole country of Japan. Periplaneta fuliginosa was captured in Honsyu (up to southern Fukushima), Shikoku and Kyushu. P. japonica was collected in northern Honsyu, such as Miyagi, Akita, Fukushima and Toyama. P. americana and P. australasiae were collected in only Okiyama. Some sylvatic cockroaches: Blattela nipponica, Onychostylus pallidolus, and Theganosipha satsumana were also collected in the limited locations. These results suggest us that domestic cockroaches habitat around houses too.

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A field-collected queen of hornet, Vespa analis that had hibernated, was cared in laboratory bestowing old combs with a hive. The queen laid some eggs early on to old combs. Some larvae grew up, and after almost a month of egg-laying, some workers emerged. After then, the colony perfectly grown up and the disintegration of the colony took place in the middle of November. The number of insects captured by workers has been estimated to be almost 20,000 individuals in a year per hive with observation of the daily behavior of workers.

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[in Japanese]

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Eighteen different materials were tested to reveal the food preference of the drugstore beetle and the cigarette beetle. The drugstore beetles selected dry yeast, mouse foods, organic fertilizer, Chinese medicine (Takusya), and oil cake. The cigarette beetles favored wheat flour, soybean flour and crumbs of bread. However, dried tofu, mixed pepper, dog foods and formulated rodenticide were not selected by the both species.

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The antidotal effect of the vitamin K₁ was examined by mixing several amounts of this chemical with 0.025% warfarin baits in warfarin-susceptible roof rats. As the result, all rats given 1.25mg and 2.5mg of vitamin K₁ were killed. In the rats given 3.75mg and 5mg, a half of them were survived. The delay of days to death was also recognized with aforementioned dosage. All rats given over 10mg of vitamin K₁ were survived in the tests for 30 days. However, all these rats were killed when vitamin K₁ free 0.025% warfarin baits were given once again.

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[in Japanese]

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Roof rats，Rattus rattus，which had periodically invaded from the neighboring area，were blocked with proofing devices or stinger brushes. Proofing is important against roof rats，which move about outside buildings even during winter in Tokyo.

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