The blood meals of engorged Culicoidesspecies taken by a light trap and animal trap at Nukabira, Hokkaido in 1963, were identified by the precipitin test. The results showed that the following species fed on the domestic mammals and bird listed below. C. sinanoensis on man, pig, horse, goat and chicken; both C. obsoletus and C. aterinervis on man, pig, horse and goat; C. dubius on man, pig and goat; both C. kibunensis and C. erairai on pig, goat and chicken. In the most predominant species, C. sinanoensis, the biting behaviour was shown to be most active ranging from the middle part of June to the beginning of July.

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1. A colony of the mosquito, Anopheles (Anopheles) sinensis Wiedemann, 1828, has been established and is now in the eighth generation. 2. Adults are housed in a screened 3′×3′×2(1/2)′cage in an insectary in which temperature is maintained at 27℃, and relative humidity is kept at 75%. 3. Sliced apples, sucrose solution (soaked in cotton pads) and a shaved, restrained rabbit are provied for food. In addition, an opportunity to feed on man is given daily. 4. Larvae are reared in aerated tap water in wooden tubs and enamel pans containing algae, Spirogyra quinina, and are fed powdered rabbit liver and powdered, high protein, laboratory rodent chow. 5. Eggs hatch in two or three days. Duration of the larval stage averages 10 days. Average duration of the pupal stage is two days. 6. Controlled light intensity and regulated duration of light and dark periods did not prove significant in establishing the colony. On the other hand, high relative humidity proved essential for maintenance of engorgement and oviposition rates and lowering the daily death rate. 7. Chief factor limiting colony size was reluctance of females to feed on rabbits and other laboratory animals. The present daily engorgement rate of about 10% of available females was achieved by rubbing human perspiration on the shaved back of the rabbit placed in the adult cage nightly.

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For the purpose to know the differences of shape or size of the egg and sexual behaviors by the living condition of the cockroach, Periplaneta japonica, the females were separated in two groups, one group contained females only and another group contained both sexes. The results obtained by the observations on these two groups, Group A the former one and Group B the latter one, were as follows : 1. Prematuration period was about 11 days in these two groups. 2. Period of egg stage in the egg sheath of A was about 32 days and two days longer than B's under the temperature of 22.2 to 29.9℃. 3. Interval of ovulation of A was 6 days and also two days longer than B's under the condition of 23.1 to 29.1℃. 4. Average number of eggs ovulated by A was a half of those of B but no difference of the size of egg sheath was observed. 5. More number of abnormal shape of egg sheath were observed in A and these egg sheath only were eaten by the roaches.

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This investigation was carried out in order to examine the relation of fly and its parasitic Hymenoptera for the purpose of practising fly contol operation at the rural districts of Tokyo. 1. Overwintering pupae of 18, 555 in number were collected in Ohme city and Chofu city, of which 9, 464 (51%) seemed to be replete by outside inspection. (Table 1) 2. These replete pupae were applied to observe the emergence of any insects from them. Flies of 3, 280 (33% to 9, 464) and 1, 998 (21%) parasitic Hymenoptera appeared. Ratio of fly to Hymenoptera was quite diverse by districts. (Table 2) 4. Of Sarcophagid flies occupied 82.7% and Calliphorid 8.6%. Of hymenopterous parasites Aphaereta sp. (2) occupied 33.7%, Brachymeria fonscolombei 30.7%, Exolytus laevigatus G. 19.7% and other species under 10%. (Table 3) 5. It is interesting that Aphaereta sp. (2) coincided with Sarcophagid in period of emergence and this parasite seems to be effective on fly control in Sawai and Minami-kosogi. (Table 2, 3) There found two types of Aphaereta (2) and of Trichopria commoda in the period of emergence. (Table 3) 6. Nakata's idea to cover the vessel containing fly pupae with a net of such mesh as Hymenoptera passable and not of flies is recommended instead of burning up the digged pupae usually practised in Japan as one of fly control measures.

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To determine the preference of ovposition of Culex pipiens (L.) to water containing larval food or other materials, a series of experiments were made using about 200 of the gravid femals housed in a cage of size of 30×30×30cm. Four jars, 6cm. In height and 9cm. In diameter, containing 200cc of water and the foods were placed in four corners of the cage, or, six beaker, 5.5cm. in height and 4cm. In diameter, containing 50cc of the test solutions were introduced in places except four corners and center of the cage. After 15 hours the numbers of egg-rafts laid in each jar or beaker were counted. The foods used in these experiments were 6 of proteins i. E. leucosin, egg albumin, casein, glutenin, zein or gliadin, 1 of peptide : pepton, 9 of amino acides : alanine, histidine, proline, lysine, tyrosine, valine, glutamic acid, asparagine or cysteine, 6 of carbohydrates : starch of white potato, starch of sweet potato, cornstarch, glucose, sugar or lactose, and others : the food for experimental animals, ebios, ethanol, urea, sodium chloride, NaOH, anmonia, acetic anhydride or HCl. Although some fluctuations observed in these results, the orders of the materials exhibit attractiveness for the female's oviposition were as follows : 0.1% of the materials added to water; Leucosin, Egg albumin>Casein, The animal food>Glutenin, Zein, Pepton, Alanine>Histidine, Proline>Tyrosin, Lysine>Valine, Glutamic acid, Asparagine>Cysteine, Starch of sweet potato, Starch of white potato, Cornstarch, Glucose, Sugar, Lactose, NaCl, Water (the following materials showed repellency for the female's oviposition)>Soybean oil, Ethanol>Acetic anhydride, Anmonia. 0.3% of the materials added to water; Cornstarch, Egg albumin, Leucosin>Pepton, The animal food>Glutenin, Casein>Zein, Glutamic acid, Glucose, Sugar, Lactose, Water, Starch of white potato, Starch of sweet potato (the following materials showed reppellency)>Gliadin>Soybean oil, NaCl, Ethanol, Acetic anhydride, Anmonia. Other experiments using 3rd instar larvae of Culex pipiens were carried out to determine the nutritious effects of the diets to the larvae. The weights of larvae that fed on foods for 1 day were measured and compared with each other. The orders of foods that produced large body weights of the larvae were as follows; 0.3% of the foods; The animal food>Leucosin, Egg albumin>Glutenin>Pepton, Casein>Zein, Starch of white potato, Cornstarch, Glucose>Sugar, Glutamic acid, Gliadin, Starch of sweet potato, Lactose, Water, Urea, Ethanol (the following materials showed larval mortalities)>NaCl>Soybean oil>NaOH>Anmonia>Acetic anhydride>HCl. 1% of the foods; The animal food, Leucosin>Egg albumin, Glutenin>Casein, Zein>Pepton>Glutamic acid>Starch of white potato>Cornstarch>Glucose, Sugar, Lactose, Starch of sweet potato, Water (the following materials showed larval mortalities)>Gliadin, Urea, Ethanol>NaCl>Soybean oil>NaOH>Anmonia>Acetic anhydride, HCl.

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Analytical studies on dieldrin resistance in field populations of larvae of Culex pipiens were done adopting two test methods. One is the so-called "ld-p line test". If a field population consisted of two or three component populations being homogeneous in susceptibility or resistance to a insecticide, and if each ld-p line (log dosage-probit mortality regression line) were separated independently, the ld-p line, or more correctly the curve, obtained from the mixed population would show one or two plateaus, flat portion parallel to the horizontal axis (see Fig.1 and Fig.2). Analyzing the position of the plateaus experimentally get from the curve, the genetical configuration of the mixed population and the component ld-p lines, such as RR, RS, SS can be estimated. By analyzing 10 field populations of C. pipiens larvae, the configuration ratios of RR (homozygous resistants), RS (heterozygous hybrids) and SS (homozygous susceptibles) to dieldrin was estimated, which were shown in Fig.3 and summarized in Fig.4 and Table 2. The other method is the so-called "discriminating test", the outline of which is as follows : Egg rafts collected from breeding sources in field were reared to 3rd or 4th stage larvae in separate bowls. Thirty (pallens type and fatigans type) or fifteen (molestus type) larvae were tested with two discriminating dosages, i. e., 0.02ppm and 0.3ppm (0.1ppm in Koniya population) of dieldrin. With 0.3ppm (0.1ppm in Koniya population), almost all of RR may be alive and all of RS and SS may be dead, and with 0.02ppm, almost all of SS may be dead and all of RS and RR may be alive. So, the rafts consisted of only RR and of only SS can be discriminated from those consisted of two or three components. In these cases, the rafts consisted of only RR may be produced from RR(P)×RR(P); and those of only SS from SS(P)×SS(P). If the frequency of RR and SS factor in P was supposed to be a and c, respectively, the appearance ratio of RR and SS rafts to all the egg rafts was admitted to be a^2 and c^2, respectively. As a^2 and c^2 can be available experimentally by the discriminating test mentioned above, a, b and c can be calculated (in this case, b=1-a-c), and RR(F_1), RS(F_1) and SS(F_1) can be calculated by the formula shown in Table 3. The configuration ratios of RR, RS and SS components in five field populations estimated by the discriminating test were listed in Table 4. In Table 5, the configuration ratios estimated by ld-p line test and by discriminating test were listed. Those methods estimated by two different tests were in good accord with each other. Summarizing the data mentioned above, it appeared surely that dieldrin resistance in larvae of Culex pipiens showed a monofactorial mode of inheritance, with the resistant factor partially dominant. This was confirmed by the crossing experiments with susceptibles and resistants, which will be reported in the other paper.

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DDT-susceptible and -resistant colonies were separated from a population of Culex pipiens molestus, namely Kawasaki population. The separating methods were as follows : Egg rafts were set in separate bowls. After rearing to 3rd or 4th stage 15 larvae were brought into the dipping test of DDT. The larvae from the egg rafts which showed higher mortality or lower one were pooled respectively to each batch. In the following generation, this method was repeated with higher discriminating dosage in the course separating resistant colony and with lower dosage in the course separating susceptible colony. After 3-4 generations, the susceptibles were colonized without exceeding more susceptible, which showed the LC-50 of 0.01-0.012ppm. The resistant colonies selected both by the separation method mentioned above and by the normal selection method under the pressure of the chemical, showed the mortality of 40% with 100ppm of DDT, though this might not be admitted to be genetical homozygous resistant colonies. The hybrids obtained by crossing resistant one and susceptible one were the intermediate of the parents, being more close to the resistant one than to the susceptible one.

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Effects of synergists to pyrethrins, and the mixtures of pyrethrins and lindane were evaluated, using houseflies with topical application method. The relative potency of synergists to pyrethrins was as follows : piperonyl butoxide, 11.06; sulfoxide, 9.62; S-421, 2.61; cynethrin, 1.07. In the mixtures of pyrethrins and lindane, the synergistic effects of piperonyl butoxide and sulfoxide increased in proportion to pyrethrins content, and effect of S-421 was influenced with neither pyrethrins nor lindane. Effect of cynethrin was of slight degree.

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Seven per cent of dimethoate is soluble in water at 80℃. It is possible that the absorption and toxicity of dimethoate in insects are more influenced by the higher atomospheric humidity than by the lower atomospheric humidity. It is also thinkable that oil added to solvent is useful to maintain insects in wet condition. A 2^3 factorial experiment on alternative storage conditions concerning the atomospheric humidity for insects before and after treatment and the adjuvant effect of soy bean oil to solvent in topical application was designed to test the toxicity of dimethoate against the common house fly, Musca domestica vicina Macquardt. The house flies were stored at either 70 or 100% relative humidity for 24 hours before treatment, and also at either 100 or 70% relative humidity for 24 hours after treatment. Soy bean oil was used as a 2 per cent (v/v) solution in acetone. The experimental data obtained (Table 1) were analysed by the method described by Finney (1952). As is seen in the estimated relative dosage values (Table 6) or relative potencies (Table 7), the effect of atomospheric humidity after treatment was the highest among the factors concerning to the absorption and toxicity of dimethoate against the house fly, and the adjuvant effect of soy bean oil was not significant.

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The autogenous type of Culex pipiens, so-called Culex pipiens molestus, has recently been an important nuisance pest in urban districts of Japan. The authors made a study on the breeding sources of the mosquito and their control method in Kawasaki city. The mosquitoes were found in 45.5% of septic tanks and in 50% of underground sewage tanks. Their control was successful by the application of 1ppm of diazinon emulsion or of Baytex granules.

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In summar of 1963, three organophosphorus insecticides, i.e., Nankor (Ronnel), Sumithion and Dipterex, were tested against natural population of non-biting stable flies, Muscina stabulans Fallen, breeding in manure under poultry cages in Saitama area. All applications were made with mortor compression sprayer at 500ml of emulsive dilution containing 0.05% of each insecticides per one square meter, and the treatments were repeated every two weeks. Fly population was evaluated by collecting the flies with paper or ribbon traps which were located at poultry farm or dwellings. All the insecticides gave good control of the stable flies breeding in poultry manure after the second treatment. After the third spraying, however, population of house fly, Musca domestica vicina Macquart, was markedly increased with the depression of the stable fly, although the house fly larvae did not breed in the chiken manure treated with the insecticides.

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The fly fauna was surveyed in the four farms of Tokyo keeping a large number of swine in May and September 1963. Flies were collected using fly catch ribbons in the same manner as the explained in former report. The observations were summarized as follows : 1) The total of collected flies amounted to 48, 254 individuals and they consist of Musca domestica, Fannia canicularis, Muscina stabulans, Stomoxys calcitrans, Calliphoridae spp., Sarcophagidae spp., and the other small-sized flies including of Drosophilidae, Psychodidae, etc. Among them, small-sized flies were ranked first, amounting to 36, 463 individuals (75.5% in total), followed by Musca domestica of 5, 686 individuals (11.8%), Fannia canicularis of 3, 813 individuals (7.9%), Muscina stabulans of 977 individuals (2.0%) and others. 2) As described in the former report, Musca domestica, Fannia canicularis and Muscina stabulans were widely observed on the inside of dwelling houses; on the other hand, Stomoxys calcitrans and small-sized flies predominated outside of the dwellings. Musca domestica were also collected considerably on the outside of dwellings, whenever the favorite diets for adult Musca domestica were available. In the case of Japanese style farm houses (opening planned houses), the number of flies in the dwellings tended to increase than that of flies in the closing planned houses. 3) It is highly likely that the number of flies in the farm in which they heap up or throw away the swine excreta and their feeds around the dwellings are numerously than that of the farm to good raising of swine. Through these observations, it was deemed that the number of flies in the such farm would be sharply decreased, if the several improvements of technical know-how for swine raising and sanitary consideration in the farm were completely practised.

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To know the comparative attractiveness of black light and white or blue ones to biting midges and mosquitoes, a light trapping was carried out during July to September, 1963, at a poultry house in the Shizuoka Prefectural Chicken Breeding Station. Black light always attracted more numbers of biting midges and mosquitoes, especially Culicoides arakawae, Culex tritaeniorhynchus, and Anopheles hyrcanus comparing with white or blue light, but the ratios of the attractiveness considerably varied with species and sex of the insects or days collected.

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The topical (LD)_<-50's> represented by μg per insect of several insecticides to brown cockroach, Periplaneta brunnea Burmeister (♀) were as follows : tech.-DDT, 323.593; lindane, 34.277; dieldrin, 6.761; diazinon, 14.454; DDVP, 5.888; malathion, 18.837.

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1) Field experiments on the insecticidal effects of 5% Nankor emulsion on larvae of mosquitoes, Culex pipiens pallens, Aedes albopictus, Aedes japonicus and Aedes togoi, in ditches and reservoirs were carried out in Kyoto City, in August, 1963. 2) By the application of 5% Nankor emulsion to the ditches at the rate of 16.67ppm of active ingredient to the whole water, all larvae and most of pupae disappeared after one day. Reapperrance of larvae occured after 16-25 days. 3) By the application of 5% Nankor emulsion to the reservoirs at the rate of 16.67ppm of active ingredient to volume of water, all larvae and most of pupae disappeared after one day. Effective period was more than 25 days, being longer than that in the ditches.

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