A collection of adult chironomid midges resting on walls of buildings on the shore of Lake Biwa at Uchidehama, Ohtsu City, was carried out using sucking tubes during the daytime on March 1 and 2,1994,during the coldest season of the year. Altogether 50 male specimens were examined after digested in 10% potassium solution, dissected, and mounted on slides in gumchloral medium. The majority of the specimens was those of Biwatendipes motoharui Tokunaga, 1965,and a few specimens of Hydrobaenus biwaquartus (Sasa et Kawai, 1987) but two new species were also included, namely Orthocladius biwainfirmus sp. nov. and Orthocladius biwaniger sp. nov.

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To investigate the possibility of cockroach control with UV radiation in a natural habitat, population fluctuation of the German cockroach before and after setting of 10W germicidal lamps was examined by the mark-recapture method. The population size at each census was calculated by Jolly-Seber's triple catch method. Results indicated that the population density decreased to about 1/13 within a month. The control effect was different among the places where the germicidal lamps were set.

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Morphometrical study on male genitalia and female wing venation of Culex quinquefasciatus Say (Baghdad origin) and Culex pipiens molestus Forskal (Mosul, 450km north of Baghdad) revealed that these mosquitoes can be differentiated from each other. Measurements of the dorsal (D) and ventral (V) arms of the phallosome (male genitalia) demonstrated that the ratios of D/V for Cx. quinquefasciatus and Cx. p. molestus were 0.337 and 1.434 respectively and the ratios of DV/D were 1.054 and -1.137 respectively on average. The measurements of R-cell and M-cell ratios of the right wing of Cx. quinquefasciatus and Cx. p. molestus showed that their means were 303.08 and 347.66 (R-cell) and 185.02 and 170.17 (M-cell) respectively. These values were significantly different between Cx. quinquefasciatus and Cx. p. molestus with marginal error in the R-cell and M-cell ratios.

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The synergistic effect of synergists, MGK 264,Synepirin 500 and piperonyl butoxide, combined with eight pyrethroids were evaluated on the adult cat flea, Ctenocephalides felis, by using the film contact method. MGK 264 was the most effective. The mixtures of eight pyrethroids combined with MGK 264 at a ratio of 1 : 5 were estimated to be 4.88,8.39,4.71,8.11,4.50,5.88,8.84,and 2.50 times as toxic as d-allethrin, permethrin, phenothrin, cyphenothrin, prallethrin, d-resmethrin, cyfluthrin, and empenthrin alone, respectively. The synergistic effects of Synepirin 500 and piperonyl butoxide combined with pyrethroids were inferior to that of MGK 264. The effects of empenthrin, cyphenothrin, cyfluthrin and prallethrin increased proportionately with increase in combination ratio of MGK between 1 : 1.25 and 1 : 20.

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Adopting the individual rearing method, the present study was carried out to observe the effect of temperatures ranging from 0 to 30℃ at intervals of 5℃ and a graded series of relative humidity from 64% up on the life cycle of Glycyphagus domesticus. Relative humidity was regulated using saturated salt solutions, NH_4NO_3 (64.5-69.1% RH), NaCl (74.7-76.0% RH), KCl (80.6-87.3% RH) and KNO_3 (91.4-93.5% RH) and water (94.0-100.0% RH). The diet was a mixture of dry yeast powder and fish meal powder in the same ratio by weight. At 30℃ and 91.5% RH or 80.6% RH, the eggs did not hatch. At 10℃ and 100.0% RH, egg hatchability was maximum. The molting rates from egg to adult were high with combinations of low temperatures and high relative humidity and low at high temperatures (above 20℃). The rate of emergence of hypopi increased as the temperature rose and the humidity decreased. At 5℃ and 87.1% RH there was high molting rate to adults, the same as at 10℃, but the life cycle was prolonged (about 130 days). At 0℃ and 81.9% RH, the eggs did not hatch until 127 days, but were hatchable. The minimum time required to develop from egg to adult was 16.3±1.7 days, at 25℃ and 94.0% RH. The lower temperature and lower relative humidity prolonged the duration of development from egg to adult. The maximum average number of eggs laid by one female, 118.7±23.3,occurred at 15℃ and 87.3% RH. The maximum reproduction index obtained by Miyamoto (1974), 158.7,was at 10℃ and 87.3% RH. The eggs were highly resistant to low temperature. They lived up to 60 days at -10℃ but for only one day at -20℃. The hypopi molted to tritonymphs at 15℃ and both 87.3 and 100.0% RH. Comfortable life conditions for G. domesticus were temperatures of 10 to 15℃ and humidity above 87.3% RH.

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Surveys of domestic mites were carried out in 21 wooden houses in and around Nagoya City from September 1983 to June 1984 at about 3-month intervals. The relationship between housing conditions and the prevalence of mites was first examined by multiple regression analysis, then the resultant standard partial regression coefficients were used as explanatory variables of cluster analysis. The mites were classified into two groups. Dermatophagoides farinae, Haplochthonius simplex, Tarsonemidae and Cosmochthonius reticulatus formed one cluster. These mites seemed to be better adapted to a relatively dry environment, since they had a significant positive correlation with the number of rooms and negative correlation with family size, except for C. reticulatus. D. pteronyssinus, Glycyphagidae, Cheyletidae and Acaridae formed the other cluster. They seemed to be better adapted to a relatively damp environment, because D. pteronyssinus, Glycyphagidae and Acaridae are known to have high humidity requirements. Glycyphagidae had a significant positive correlation with family size and working housewife, and negative correlation with the number of rooms and age of house. Housing conditions were also classified into two groups. One group consisted of the number of rooms, types of flooring and heating system, age of house, and air conditioning. These were considered to be dry factors. The other group consisted of family size, working housewife, house-cleaning frequency, and type of bedding. Family size and working housewife were considered to be humid factors. These results suggested that the difference in the prevalence of mites was a reflection of the interrelationship between the biological characteristics of mites, especially their humidity requirements, and the degree of dampness in houses largely influenced by household activities and dwelling space.

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In order to elucidate the housing conditions and prevalence of mites characteristic of homes with allergic children, surveys of domestic mites were conducted in 22 wooden houses in and around Nagoya City from September 1983 to June 1984 at about 3-month intervals. Allergic children suffering from bronchial asthma or atopic dermatitis and positive to house dust mites (RAST scores, 3 to 4) were found in 11 homes. They had been given a set of instructions for preventive measures against allergy. The remaining 11 homes had no allergic children and served as controls. The data were examined by Student's t-test of mean difference and linear discriminant analysis. There was no significant difference in the housing conditions between the two groups of homes, except that flooring scores were significantly lower in the homes of allergic children. In some of them, floors of tatami or carpet had been replaced with wooden or plastic floors as a preventive measure. The flooring score was also selected as a significant variable in discriminating the two groups of homes. The classification accuracy was 90.5% before the selection of variables and 76.2% after the selection. While the density of D. farinae and the total number of mites were significantly less in the homes of allergic children than in the control homes, Simpson's indexes of diversity were significantly higher in the former. The diversity index and the densities of D. farinae and Acaridae were selected as significant variables in discriminating the two groups of homes. The classification accuracy by the analysis of mite prevalence was 100% before the selection of variables and 90.9% after the selection. The lower flooring scores most likely explained why fewer D. farinae and the lower total number of mites were detected from the homes of allergic children than from the control homes. The results also suggested that the indoor air humidity in the homes of allergic children might be higher than that in the control homes.

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Sciria tanegashimensis sp. n. (male, female) and Philosepedon monstruosus sp. n. (male) are described with differential diagnoses and illustrations. The generic name Sciria Enderlein, 1935 is restored to a valid genus from a synonym of the genus Telmatoscopus Eaton, 1904. All the known species of Sciria are listed.

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The fauna and distribution of the blackflies in Niigata Prefecture were studied based on the collections of larvae and pupae from streams and adults flying around the collectors at 111 localities in the summer of 1992. A total of 11,497 blackflies, 9,774 larvae, 1,702 pupae and 21 adults, were collected at 90 sites. The fauna composed of 18 species belonging to 2 genera. Four species, Simulium (Gomphostilbia) shogakii, S. (Gnus) malyshevi, S. (Eusimulium) sp. H. and S. (E.) sp. Y., were newly recorded from Niigata Prefecture. The most abundant species was S. (Simulium) japonicum (38.6%), followed by S. (Nevermannia) uchidai (21.9%), S. (S.) suzukii (13.2%), S. (Odagmia) aokii (8.2%) and S. (Gom.) shogakii (5.3%). The most widely distributed species was S. (S.) japonicum (60 sites). Other four species, S. (N.) uchidai (60 sites), followed by S. (S.) suzukii (51 sites), S. (O.) aokii (31 sites) and S. (Gom.) shogakii (26 sites), were also collected at many localities.

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Toxorhynchites towadensis (Matsumura, 1916) is well known to have peculiar bionomics and to be a bio-index species of the rich forest. Although this species has a wide distribution in Japan, there are only 5 points of distribution hitherto known in Hokkaido. The authors collected this species at another 4 localities in Hokkaido. Of these localities, Okushiri Island is new and Fukushima, Samani and Ebetsu are the most southern, eastern and northern distribution records of this species in Hokkaido respectively.

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[in Japanese]

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A case of dermatitis due to slug caterpillar of Lotoia lepida, in Saitama Prefecture, was reported. Many small erythematous maculopapules with itching were observed on the forearm and cubital fossa.

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We evaluate the effectiveness of a stream of hot air from a hair dryer for killing eggs and adults of human body lice, Pediculus humanus corporis. All adult lice treated with hot air at 50℃ for 5min did not survive, although all adult lice treated with cool air at 27-28℃ for 5min survived normally. In the exposure of hot air at 55℃ for 1min or more all adults died. The stream of hot air at 60℃ also killed all adults even when exposure was brief (for 30sec). Louse eggs treated with hot air at 55℃ for more than 90 sec never hatched. The escape behaviour of adult lice treated with hot air at 50℃ was observed and the average speed travelled by a female adult was 6.9mm/sec and by a male adult 7.3mm/sec.

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