Investigations were carried out on the fauna and distributions of black-flies in Kyushu in 1971-1974. A total of 2,072 pupae and 2,759 larvae were collected from 144 sites in 12 districts. Eighteen species and 1 subspecies were found, of which Simulium (Eusimulium) aureohirtum, S. (E.) sasai, S. (E.) subcostatum koshikiense, S. (E.) sp., S. (Gomphostilbia) ogatai and S. (Gnus) daisense were recorded for the first time from Kyushu. This brought the total number of Simuliidae in Kyushu to 25. The most abundant and widely distributed species are : S. (G.) bidentatum, S. (Simulium) arakawae, S. (Odagmia) aokii, S. (E.) uchidai, making up about 70% of the total number of specimens collected. Notes on geographical and vertical distributions of 19 taxa of black-flies in Kyushu were given.

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The effectiveness of a new acute rodenticide, Pyriminyl (RH-787) to rats and mice was investigated. As a result, the LD_<50> values of technical were 24.4-26mg/kg in male rats, 12.2-27.9mg/kg in female rats, 68.8-90mg/kg in male mice, and 56-68mg/kg in female mice. These values resemble closely that of thallium sulfate and zinc phosphide which are being used practically at present. In the experiments conducted using only 2% baits, all mice died in 1 day later and all rats died within 5 days. Secondly in the experiments of the choice test between 2% baits and rolled barley, no difference of acceptance was observed on mice, but rats showed a little low acceptance to poison baits. In the preliminary experiments using 1% powdered baits and powdered nonpoison baits, however, no avoidance to poison baits was observed on rats and ll died within 2 days. From the above described, Pyriminyl might be anticipated as a promising acute rodenticide in future by adding further more information concerning formulation and concentration.

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Immunological reactions were performed on asthmatic children living in and around Tokyo with the extract of house dust mite, Dermatophagoides pteronyssinus, as antigen. Mite fauna in house dusts of the patients was examined and relation between the mite fauna and immunological findings was studied. Higher than 70% or more positive rates were obtained in skin test and radioallergosorbent test (RAST) either to house dust or the mite antigens. On the other hand, passive hemagglutination test and double gel diffusion test against the mite extract were all negative. House dust was collected from the residences of 17 skin test and RAST positive patients and 10 negative asthmatic children. Pyroglyphid mites constituted 70-90% of the mite fauna and constitutional pattern of other mites did not differ in both groups. However, number of mites found in dusts per square meter for a week differed significantly (p<0.05). This study comfirms the importance of the house dust mite in children's asthma and shows that absolute number of mites in the dust plays an important role in the sensitization of children with substantial figure.

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Despite a relatively high prevalence of pregnancy and numbers of embryos produced Rattus norvegicus has a very restricted distribution in the city of Rangoon. Significant changes in the distribution of this rat from that reported 30 years ago were not detected. It is suggested that R. norvegicus distribution and abundance are related to the presence of large numbers of Bandicota bengalensis. The majority (87.2%) of the R. norvegicus captured were infested with fleas. Three species of fleas were recovered : Xenopsylla cheopis, X. astia and Ctenocephalides felis. The possible importance of R. norvegicus with regard to rodent-borne diseases is discussed.

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Some ecological investigations on biting midges, mainly Culicoides nipponensis, were carried out with the light trap or dry ice trap in the cowshed and the paddy area in Mie Prefecture from 1972 to 1975. Results obtained were summarized as follows; 1) Biting midges captured with light trap in the cowshed were C. nipponensis, C. arakawae, C. pulicaris, C. sigaensis, C. odibilis and unknown one, 99% of them were C. nipponensis from June to September. The number of C. nipponensis increased in June and decreased rapidly in October. 2) Two-hourly collection in the cowshed and the surrounding paddy fields were carried out with light traps. From the experiment it was found that there was the difference in the host preference between C. nipponensis and the other species. 3) Biting midges were captured by dry ice traps at 14 points on paddy area in 1974 and 1975. The composition of species was nearly similar to that by the light trap in the cowshed, and 96% of all were C. nipponensis. There were some points where C. nipponensis was captured in large numbers or in small numbers. It is likely, therefore, that C. nipponensis does not inhabit uniformly in all the census area.

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Allied species of the subgenus Leptotrombidium are often very difficult to classify. The author attempts to describe a new species belonging to this subgenus with special emphasis on the morphological stability and the distributional character covering a northern broad area of Honshu, Japan. Leptotrombidium (Leptotrombidium) asanumai n. sp. Body reddish orange, the general appearance of typical Leptotrombidium. Gnathosoma : Palpal pilous formula N-N-BNN. Scutum : The posterior margin is gently curved. AM seta and PL setae (longer than AL setae, measuring 74 long in holotype) have minute and sparse spikes. Sensillae are placed slightly posterior to the level of PL setae, and the proximal half of them is naked. The scutal measurements are almost same in specimens from four different localities. Dorsal setae : Pilous formula is 2-8-6(7)-6-4(6)-4-2(32-35) with little variation. They have the similar spikes as PL setae. Humeral setae measure 69μ long in holotype. Ventral setae : Comprise about 20 anteroanal setae and about 10 posteroanal setae with the similar spikes as DS setae. Coxal setae : One seta is out of anterior margin of coxa III. Ecological data : Eighty-eight larvae ex Microtus montebelli, 1 larva ex Apodemus speciosus, 1 larva ex Rattus norvegicus in 7 localities of Aomori Pref., July 1967 to Nov. 1976; 457 larvae ex M. montebelli in Takanosu, Akita Pref., Aug. 1969. The peak of seasonal occurrence was found from July to November by the author (1976) in Hirosaki Park. Type specimens : Holotype and 7 paratypes preserved in the Department of Parasitology, Hirosaki University School of Medicine, Hirosaki, Japan. Remarks and specific diagnosis : This mite is identical with L. sp. No. 50 by Sasa (1956) and L. sp. by Ito and Obata (1961). Historically, Asanuma et al. first obtained it in Oze, Gunma Pref. in 1950,then, Obata et al. found it from a locality of upper valley of the river Shinano, Niigata Pref., but it remained unnamed until today. This mite differs definitely from two related species L. akamushi and L. scutellare, because the scutal size and situation of sensillae are dissimilar, PL setae are relatively longer, the bodies of AM, PL, DS and VSP setae are more stout (4.5-6μ wide vs. about 3.5μ wide in L. akamushi), the spikes are more minute than those of the latter, and also the number of DS setae are less. The author found no difference between the present materials and the specimens of L. sp. No. 50 taken from Oze which was kindly supplied by Dr. K. Asanuma. The species is dedicated to Dr. Kiyoshi Asanuma, The National Science Museum, Tokyo, for the memory of his continual contribution to medical acarology.

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Surveys were conducted in order to clarify the mite fauna in the living environment of asthmatic children in Japan. Dust samples were collected from floor and beddings (Futon) of asthmatic children who were sensitized by the house dust mite (Dermatophagoides). Mites were collected by the method flotation and sedimentation using Darling's solution (glycerin and saturated NaCl) after sieving on 9 and 200 mesh sieves. Ten samples in summer and 13 samples in winter were examined. Average number of mites in 0.5g of fine dust on floor were 168 in summer and 54 in winter. Mite fauna did not differ much from previous reports : Dermatophagoides pteronyssinus and D. farinae were dominant constituting 79% in summer and 66% in winter of the total mite number. Average weight of Futon dust were 0.28g in summer and 0.71g in winter but number of mites contained in Futon dust did not differ much being 72 in summer and 76 in winter. Mite fauna as a whole in Futon dust was same to that of floor dust. Floor dust of a room for new-borns in a hospital and a well-kept patient's house contained relatively few mites however mites were detected in the air. Dusts of air cleaner revealed some mites including D. pteronyssinus. These findings suggest to encourage patients to keep clean of floor and Futon to avoid mite as much as possible.

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A new subspecies of the biting midge, Leptoconops (L.) nipponensis oshimaensis is described based on the female specimens collected from Amami-oshima Island, Japan. This is differentiated from the type species, L. (L.) nipponensis Tokunaga, 1937 by the different value of antennal ratio, the longer bristle-like setae on vertex and on prescutellar area of the thorax and the stoutness of the spines on the basitarsus of fore leg.

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Haematopota hikosanensis, a new species is described from Kyushu Island. This species is closely related to H. toyamaensis Watanabe, Kamimura and Takahasi, but can be distinguished from it by the clearly marked median spot and roughly rounded side-marks on frons, straight dorsal margins of antennal scape, a greyish patch on scutellum and dark brown abdomen without any pale marginal bands on each tergite.

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A Japanese leech Hirudo nipponica was examined morphologically by means of the scanning electromicroscope. The most remarkable characteristics are as follows : The minute teeth or denticles had been described by many workers to arrange in " row" on each of the three jaws, but the present observation revealed that "the row" of teeth actually consisted of two rows of denticles and that there were occasionally observed leak, defect and deplacement of the denticles and disarray in the denticular arrangement. A great number of minute tubules are situated between the two rows of denticles, which seemed to be the openings of the salivary gland. The eyes are five pairs in number and concave on the surface, where a pore is observed in the center. Many minute pores are distributed on all the surface of jaw and body, especially abundantly near the annulus grooves and, further, on the inner surface of the anterior and posterior suckers. These minute pores are considered to be the orifice of the mucous gland or that of the excretory canal. The last annulus groove is wide and has a few folds. The penis has many small processes on the surface.

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An investigation on the quantity and the sugar composition of sucked nectars, and the parous rates was conducted on the blackflies collected at Kohzu ranch in Gunma prefecture from June 22 to 24,1974. Five species of the blackflies were recognized. Female of Prosimulium yezoense exhibited the highest nectar-sucking rate of 91.8%, followed by female and males of Simulium arakawae, 90.2 and 87.0 respectively, females of P. jezonicum, 86.2%, the female of S. japonicu, , 81.7%. and females of S. iwatense, 70.0%. These rates were much higher than those observed in horse-flies or mosquitoes. The volume of fully-sucked nectar was 1.7-2.6 l in 3 species of Genus Simulium and 2.4-2.9μl in 2 species of Genus Prosimulium, the variation being dependent on the body size. The sugar contents per 1μl nectar recovered from diverticulums of fully-sucked individuals were 167 to 792 g or 16.7 to 79.2 percent, when analyzed by phenol sulfuric acid method. Paper chromatographic analysis revealed 6 different sugars; fructose, glucose, sucrose, maltose, melibiose and raffinose, were in their sucked nectars, the composition of which varied individually. More than half of the fully sucked blackflies possessed 4 or 5 different sugars excluding either sucrose or sucrose and raffinose, although sucrose was always found in nectars sucked by horseflies at the same field. This indicates the species difference in nectar sources. The parous rate of 36.7% in S. iwatense was significantly low in contrast to the other 4 species which showed the value ranging from 65.0 to 71.3%. The rates of individuals having sac-like relics, however, relatively high in all 5 species, the lowest being 46.2% in S. japonicum. These high rates may be attributed to fact that the trapping station was located close to a stream (approximately 20m).

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In order to know the most efficient density for rearing of German cockroaches Blattella germanica (L.) to obtain a number of favorable test insects as possible for insecticide test, dencity effect was examined. Cockroaches were reared in plastic containers (10×16×15.5cm), provided two boads (10×5cm) as a shelter, under laboratory conditions of 25±1℃, 50-60% R.H. and 15 hours illumination a day. 1,2,10,50,100,500 and 1,000 newly hatched nymphs were admitted to each container. The susceptibilities of the emerged adults to fenttrothion were examined by the topical application method. Results were as follows : Generally, the nymphal period was slightly prolonged and adult emergence decreased in accordance with increasing density. The body weight and the length of hide tibia showed the maximum values in the moderate density. The adult life span and the reproductivity were remarkably influenced by densityssize. The female adults, bred in 2 individuals during nymphal stage, survived for 226.0 days and produced 193.8 nymphs per female in average. On the other hand, the female bred in 1,000 individuals, was most inferior surviving only for 107.7 days and producing only 30.0 nymphs per female in average. Due to high density, individuals with damaged wings and antennae increased significantly. There was no significant difference on the susceptibility to fenitrothion among different densities. But insects which were reared under the high densities were slightly smaller in size, and slightly susceptible than others. The number of offsprings per rearing container was the biggest in the container contained 500 individuals, producing 15,737 offsprings. It seemed that taking account of insecticide susceptibility not depending on density, the most preferable rearing density for insecticide test, is 1-2 individuals per 1(cm)^2 of available space in container.

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Many Anopheles sinensis were found in Kyushu, Shikoku and Honshu but only few in Hnkkaido. A. sinensis "E (Engaru)" which is a possibly new sibling species of A. sinensis was found only in Hokkaido especially in the northeastern parts. A. lesteri was collected in very low numbers in the southwestern parts of Japan, where this species used to be common, but was also obtained at Yomogita in Honshu, and in Hokkaido. A moderate number of A. sineroides were obtained in Karuizawa and a small number of them in Hokkaido.

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Steatonyssus longispinosus Wang, 1963,infesting the house bat, Pipistrellus abramus Temminck, is redescribed. The occurrence of Steatonyssus spinosus Willmann, 1936,and Steatonyssus superans Zemskaya, 1954,in Japan is recorded. The key for the differentiation of all the parasitic stages of these species is presented.

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Since 1972 the chironomid midges, prevalent at the near renovated urban worst rivers, have been becoming a serious nuisance in this country. By the light traps run at the infested sites of the river Kanda, Tokyo, 3 species of the midges referable to 2 genera were recognized. The dominant species was always Chironomus yoshimatsui Martin & Sublette. According to the results obtained in 1972-1973 C. yoshimatsui emerge out during a long period from late March to mid December showing definite peaks of emergence in every 2-3 weeks, the maximum population size reaching in late August-September. One adult emergence cycle is approximately in accord with that obtained in laboratory. In 1974 higher peak in prevalence showing in late June-early July and following peak appeared in September. On the other hand large numbers of the midges were prevalent successively from mid June through October and a curve of plateau has been showing in the trend of emergence since 1975. It was also confirmed experimentally that the range of infested area is within 100 meter distance along the river side.

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The seasonal prevalence of flies was studied at a farmhouse located in the suburbs of the City of Daegu in Korea from April 1 through December 31,1964. Glass traps and sticky ribbons were used for collecting flies. The total number of flies collected was 100,961 of 24 species (41,287 males and 59,674 females). Predominant among the species collected were Musca domestica (39.5%), Phaenicia sericata+P. cuprina (17.7) and Boettcherisca peregrina (14.5). These three made up 72% of the total catch. Seasonal prevalences of flies show that the highest peaks of the fly abundance were observed to be in June or July at all sites for traps and other peaks in April, September or October. Three peaks were observed at the sites for ribbons. It was noted that the differences in species, collecting methods and their sites resulted in different patterns of seasonal prevalences. Breeding places and media of flies in Korea were discussed in view of the mode of life and the climate of the country. Known media of the 33 species were described.

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[in Japanese]

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[in Japanese]

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