Electrophoretic studies of isozymes in Simulium ochraceum, the main vector of Central American onchocerciasis, were performed using starch gel electrophoresis. A total of six larval and adult populations originating from four localities in Guatemala (a non-endemic area, Finca La Ruda; a low-endemic area, Finca Rincon; and two high-endemic areas, Finca Brote and Finca Recreo) were analyzed electrophoretically. The enzymes examined were adenylate kinase (AK), alkaline phosphatase (ALP), glucose phosphate isomerase (GPI), hexokinase (HK), isocitrate dehydrogenase (IDH), leucine aminopeptidase (LAP), malic enzyme (ME), and phosphoglucomutase (PGM). Of the eight, six enzymes, AK, ALP, HK, IDH, LAP, and ME showed no variation either within or among populations. The other two, GPI and PGM, were found to be highly polymorphic in all six populations. The X^2 test for fit to Hardy-Weinberg equilibrium (HWE) revealed the distribution for the phenotypes of the two polymorphic enzymes not to be significantly out of the HWE. Averages of values of proportion of polymorphic loci (P) and heterozygosity per individual (H) of the six populations were 0.234 and 0.084,respectively, each of which was almost the same value as that for different groups of organisms. Genetic diversity among populations was measured by F_<ST> and G_<ST>, both of which showed that the non-endemic population from Finca La Ruda (D1) was greatly differentiated genetically from the other five populations. The estimates of genetic distance also showed that the D1 population was very distant from the other populations.

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A comprehensive range of organic compounds has been investigated as possible attractants for the seaweed fly, Coelopa (Fucomyia) frigida. The range involved various compounds in different chemical classes and each compound was separately evaluated quantitatively. The compounds which were found to attract significant numbers of the fly were (in the aliphatic halides) chloroform, methyl iodide, methylene chloride and propylene chloride; (in the aliphatic nitros) 2-nitropropane; (in the aromatic hydrocarbons) benzene; and (in the alicyclic hydrocarbons) cyclohexane. In particular we found that chloroform and benzene were the two most effective attractants. In the aliphatic classes, the attractiveness increased with decreasing boiling point of the compounds. In the aromatics, the attractiveness increased with decreasing carbon number. The aliphatic sulfides, nitro compounds, aldehydes, carboxylic acids, aromatic amino compounds, aromatic carboxylic acids, phenols, terpenes, and proteins were all found to be unattractive. The volatile compounds of the decayed laver were isolated and identified by the gas chromatographies, GC-FID, GC-FPD, and GC-MS. The analysis revealed the following constituents (in descending order of quantity); hydrogen sulfide, sulfur dioxide, methyl mercaptane, dimethyl sulfide, dimethyl disulfide, and traces of either two of the following three compounds; methyl-mercaptomethyldisulfide, mercapto-(2-mercaptoethyl) sulfide, and methylthiomethylmer-captosulfide. There was no relation between the volatile components of the decayed laver and the screened attractive compounds. We therefore consider that the seaweed fly must be attracted through its unknown taxis to certain organic compounds, which are unrelated to the volatile components of the decayed laver.

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Twenty-one species of non-muscoid Diptera (Psychodidae, Phoridae, Sphaeroceridae, Ephydridae, Milichiidae, Chloropidae) were bred from dead snails, Achatina fulica, in West Malaysia, and four species from the same habitat in Northern Thailand. Information is given on the breeding sites, pattern of occurrence, development time, hymenopteran parasitoids, and medical and veterinary importance of the species.

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Mosquitoes were collected by light traps at several places in Okayama Prefecture since 1950. Principal species collected were Culex pipiens pallens, Culex tritaeniorhynchus and Anopheles sinensis. The numbers of collected mosquitoes were integrated during a common sampling period (from 2 June to 1 September). Chronological changes of the annual integration values in each species differed between the sampling sites. The numbers, however, prominently decreased towards 1981 in all of the three species, especially in Cx. tritaenioryhnchus.

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The reproduction and distribution of Tyrophagus putrescentiae were observed in different flooring materials in the laboratory. When pulverized, such flooring materials as straw mat, carpet and insulation board did not seem to be so suitable for reproduction as the flour of the rat food, which is commonly used to culture mites in the laboratory, but the mite maintained their population density at the level of ca. 100 to 2,000/g for a few months, although their density differed by the materials. Assuming the reproduction index of the mite in the pulverized straw is 100,that in straw+rush was 175.4 followed by 106.4 in rush alone, 55.4 in insulation board+rush and 25.3 in insulation board alone. Population density of the mite in the pulverized carpet was as low as 95 to 460/g, but when 10% of the flour of rat food was added, it increased about 10 times. Crawling mites on the surface of the straw mat reached the peak in number 4 to 5 weeks after a small number of mites were initially placed on the mat. More mites were always recovered from the superficial part of the mat than from the inner part, but the number of mites that invaded into the inner part of mat increased as the number of mites placed initially became large. Some mites were found in the inner part of the hard insulation board also, 4 weeks after the initial placement of mites on the surface.

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Compositions of the venomous principles in worker and queen honey bees (Apis mellifera) during their maturation were examined in two criteria by the pattern analysis of electrophoresis and that of high performance liquid chromatography. The venom of well matured worker bee showed electrophoretically 13 proteinous bands including those corresponding to phospholipase A_2,melittin, apamin and MCD-peptide. On the other hand, in the queen bee venom, the band corresponding to MCD-peptide was not detected but the two additional unknown components were found. The amounts of the venomous components in both worker and queen bee venoms increased remarkably within 14 days after eclosion.

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The eight possible isomeric forms of prallethrin, which is an analog of allethrin containing a propargyl group in place of the allyl group, were in detail examined for biological activities. The ester, which has the d configuration in the ketoalcohol moiety and the d-trans configuration in the chrysanthemic acid moiety, showed the best performance with 660 times the toxicity over the lowest toxic isomer of l-l-cis configuration from the comparison on LD_<50> values by topical application against houseflies, followed by the d-d-cis configuration. Other isomers were also studied for the order of toxic magnitude.

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The effect of temperature on the oviposition and development of the two Haemaphysalis species, H. longicornis and H. flava was observed under laboratory conditions. The mean number of the deposited eggs per mg body weight of H. longicornis female increased at a high temperature of 30℃, while it decreased at 30℃ in H. flava. The egg hatchability of H. longicornis was high at all temperatures from 15 to 30℃, but that of H. flava was reduced at 30℃. The survival rates during the larval and nymphal post-parasitic period of both species were not significantly different at all temperatures from 15 to 30℃. The pre-oviposition period was short at 30℃ in H. longicornis, but very long in H. flava. The incubation period of eggs became shorter with increasing temperature in H. longicornis, but in H. flava it was longer at 30℃ than at 27℃. The larval and nymphal post-parasitic periods of both species were short at higher temperatures. In H. flava, the larval post-parasitic period was shorter at high temperatures, but the nymphal post-parasitic period was longer at all temperatures, than in H. longicornis. In both species, the developmental zeros for each developmental stage were calculated from the regression equations between developmental velocity and temperature. The total effective temperatures from egg to adult excluding pre-parasitic and parasitic periods in each stage were 820.0 and 961.5 day-degrees for H. longicornis and H. flava, respectively.

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The female reproductive organ of Chrysomya megacephala F. consists of paired ovaries, lateral oviducts, a common oviduct, 3 spermatothecae and paired accessory glands. Each ovary is formed of about 100 to 110 polytrophic ovarioles. Externally, each ovariole is enclosed by a thin tunica propria. The common oviduct has syncytial epithelium lined by a thin intima. The duct has both longitudinal and circular muscles. The vagina is distinguishable into anterior and posterior portions. The posterior vagina has longitudinal as well as circular muscles but the anterior vagina has only circular muscle layer. Out of 3 rounded spermatothecae the 2 of one side are loosely bound together. Each spermatotheca is bounded with cuboidal epithelial layer. The cell has a prominent vacuole in the apical half which is filled with secretory material for the benefit of spermatozoa. The paired accessory glands open separately into the genital chamber. These glands show maximum activity during the breeding period.

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The tabanid faunas of Teuri and Yagishiri Islands, Hokkaido, Japan were surveyed by collecting female adults with a mosquito-net trap baited with dry ice, on August 2 and 3,1984. Only two autogenous species (Tabanus rufidens and Haematopota tristis) were obtained on Teuri Island, while no tabanid was found on Yagishiri Island. Twelve species were collected in Shosanbetsu village and Tomamae Town of Hokkaido which are close to respective islands of Teuri and Yagishiri. The tabanid faunas of the five islands were compared with that of the main island of Hokkaido and the derivation of tabanid faunas in these small islands was discussed.

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Effect of solvent on the larvicidal activity of juvenile hormone active compound, S-21149 (propionaldehyde oxime ο-2-(4-phenoxyphenoxy)-ethyl ether), was examined. Emulsifiable concentrate or ethanol treatment gave a higher activity than acetone treatment. This was thought to be due to the production of a lower active compound by the reaction of S-21149 and acetone.

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An investigation was made to know the seasonal fluctuation of Aldrichina grahami (Aldrich) in Aogashima Island, Tokyo, from December 1982 to December 1984. A trap baited with horse flesh was set at a station on a hill at 300m above sea level, and the numbers of flies trapped were counted once a month. Adult flies were captured from November to June or July, but none was seen for succeeding 3-4 months. It is not clear that females captured in autumn could aestivate in the island or migrated from the nearest Hachijo Island.

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[in Japanese]

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The susceptibility levels to several insecticides in the adults of the WMC colony of Tyrophagus putrescentiae were examined by the filter paper contact method. Fenthion and fenitrothion were found to be effective among the insecticides tested. The values of LC_<50> were 2.0 and 4.2ppm in fenthion and fenitrothion, respectively. No appreciable difference in the susceptibility to fenthion was recognized between three laboratory colonies of this mite (WMC, SNT and TMI).

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