The migration of blow flies from the lowland to the highland was investigated at Mts. Tateyama in Chubu Sangaku National Park in 1985 and 1986. To capture the adult flies, 30 bait-traps were set between altitudes of 420 and 900m along the valley of Shomyo River at the foot of Mts. Tateyama. The capturing period was from May 8 to June 12 in 1985 and from April 30 to July 2 in 1986. The dominant species were Calliphora nigribarbis and C. vomitoria. A total of 8,909 and 13,990 adults was marked and released in 1985 and 1986,respectively, at an altitude of 660m. Bait-traps of a permanent type were set at altitudes of 1,000,1,500,2,000,2,300,2,500 and 2,700m for continuous recapturing. Eighteen and 17 females were recaptured in 1985 and 1986,respectively, by these traps of higher than 2,000m. All of them were C. vomitoria. Only one marked female of C. nigribarbis was recaptured in 1985 at 1,500m. In 1986 additional recapturing was conducted by the bait-traps at 420 to 900m along the valley of Shomyo River. C. vomitoria flies were never recaptured at lower altitudes than the release place. On the other hand, C. nigribarbis flies were recaptured at both higher and lower altitudes than the release place. These results indicate that C. vomitoria has a strong tendency to migrate to the alpine and subalpine zones in early summer and may stay there during the summer season, whereas C. nigribarbis does not have such steady migration pattern.

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While the authors were studying the biology and control of the chironomid midges (yusurika, in Japanese) emerging from the moat of Hiroshima Castle and other areas of Hiroshima Prefecture, the following three species of taxonomic interests were collected and identified. These are Hirosimayusurika tsujii gen. et sp. nov., Eukiefferiella fujisexta Sasa, 1985,previously known as a single male, and Okinawayusurika akiensis sp. nov.

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Two new species of Culicoides biting midges, C. aomoriensis and C. tatebeae, are described and figured from the material collected during a survey of biting midges in Aomori Prefecture, Japan.

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To seize the prevalence of B. burgdorferi in Nagano Prefecture, we examined I. persulcatus and I. ovatus ticks for spirochetal infection in 1990. The ticks swept at 20 sites were tested by culturing their midgut tissues or by an indirect immunofluorescence assay using the monoclonal antibody, H5332. The spirochete was detected in the ticks from 18 sites. The infection rates for the adult ticks of I. persulcatus and I. ovatus were 21.3% (68/319) and 25.1% (76/303), respectively. Such the high prevalence of the spirochete in the tick vectors was comparable to that in the Western Europe.

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Chromosome observations of triatomine bugs known as medically important vectors of American trypanosomiasis (Chagas' disease) were attempted. We demonstrated by the C-banding technique that a Brazilian strain of Triatoma infestans includes at least three cytotypes in terms of constitutive heterochromatin polymorphism. We found cytological evidence that there is a significant difference in cytotype frequencies between observed values and expected ones from Hardy-Weinberg principle. This evidence suggests a genetic regulation or an incompatibility mechanism between cytotypes, which will serve as hopeful cytological markers for vector control.

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The effect of encasement of bedding with high-density fabric was examined in an effort to prevent infestation with house-dust mites. The study was conducted using the bedding of 22 asthmatic patients. They were divided into 2 groups; floor bedding (futon mattress), blanket and pillow encased with a high-density fabric were supplied to 1 group, and to the other group bedding was supplied without such encasement. Both of the encased and unencased bedding were wrapped in cotton sheets. Dust was collected from 2m^2 of the upper surface of the cotton sheet before and 4 weeks after the encasement. The mites found were mostly Dermatophagoides. The numbers of both live and dead mites decreased significantly by the encasement. The proportion of futon mattress infested with more than 10 live mites/2m^2 was lower in the encased (0/8) than in the unencased bedding (2/14) after 4 weeks. That with dead mites was also lower in the encased than in the unencased bedding (1/8 and 9/14,respectively).

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The effects of juvenile hormone analogue (methoprene, JHA) on ovarian development of the reproductive-diapausing parasitic fly, Melinda pusilla (Villeneuve) (Diptera : Calliphoridae), were investigated. The ovarian development of reproductive-diapausing females in the early stage of overwintering was accelerated by JHA treatment dose-dependently from the pre-vitellogenic stage to the vitellogenic stage, although the effect of a single dose (1μg) of JHA treatment was not enough to terminate the reproductive diapause. Two or 4 repeats of JHA treatments (1μg/one dose) at 5 days' intervals induced 100% egg maturation within 10 to 20 days after the treatment. In fermales in the middle stage of overwintering, a single dose of JHA treatment accelerated follicle development but did not accomplish egg maturation. In the late stage of overwintering, in which 80% of the females had matured eggs in accordance with the reproductive diapause termination, JHA treatment enhanced moving of the matured eggs into the uterus. These results suggest that JHA works dose-and stage-dependently on the termination of reproductive diapause in overwintering M. pusilla.

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[in Japanese]

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[in Japanese]

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Nineteen species of Tabanidae belonging to 7 genera in the collection specimens by Mr. Azusa Tanaka are listed. Stonemyia enokizonoi ishizuchiensis from Mt. Odaiga-hara, Nara Pref., is the new record outside Shikoku. Hybomitra ishiharai, a rare species in Honshu, was from Minoo, Osaka Pref. Hirosia sapporoensis from Mt. Tsurugi is the first record in Shikoku.

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