A new species of the Listrophorid mites, Alabidocarpus fujii n. sp., was found from the Japanese long-winged bat, Miniopterus schreibersii niponiae, collected at Miyazaki, Shizuoka and Chiba, Japan. This species is most closely related to A. calcaratus Lawrence, 1952, but the two species deffer in the shape of propodosomal shield and of tarsi of first and second legs. According to the key to the species of Alabidocarpus by Pinichpongse, this new species falls into A. longipilus Pinichpongse, but A. fujii is much larger and has minute setae on mid-dorsum at the level of leg IV. Holotype : Female is deposited in The National Science Museum (Zoology), Tokyo, Japan; (NSM-AC-P 280).

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Using a colony of Laelaps nuttalli collected from rat in the area of epidemic haemorrhagic fever the authors studied its food and blood feeding habits under laboratory condition. Adult and 1st and 2nd nymph of this species fed well on oil in fluid group of food and in solid one they fed very well on boiled egg yolk of chicken, and blood cake (human, rat and chicken) were engorged into their digestive organs. The mite did not attempt to feed unbroken skin of the hosts.

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1. Tests were conducted to determine susceptibility of eight species of mosquitoes to infection with microfilariae of Dirofilaria immitis. Highest infection rates and largest numbers of infective larvae were found in specimens of Aedes togoi fed on an infected dog and examined 12 days thereafter. Other species tested were Culex pipiens fatigans, Culex pipiens pallens, Culex tritaeniorhynchus, Aedes albopictus, Aedes aegypti, Armigeres subalbatus, and Anopheles sinensis. 2. There were no outstanding differences in D. immitis infection rates among Aedes togoi of four age groups allowed to feed on an infected dog. 3. Microfilariae in peripheral blood of a dog under treatment for dirofilariasis during a 21 day period remained infective for mosquitoes, Aedes togoi, fed on the dog on 10 days during the course of treatment. Decline in numbers of microfilariae in blood of the dog was much more rapid than decline in numbers of infective immitis larvae in mosquitoes which had been fed on the dog and dissected 12 days thereafter. 4. In surveys of microfilaremia among dogs at Kochi, Shikoku the factors which showed most striking correlation with high incidence of infection with D. immitis were age and habitat. Dogs from wooded foothills outside Kochi City proper showed a much higher microfilaremia rate than those from urban Kochi and from a seaside area near the city. Short haired dogs showed an infection rate nearly twice that of long haired animals, and males were infected nearly twice as frequently as females. 5. Only eight of 1, 813 adult female mosquitoes of seven species obtained in light traps, and in resting and biting collections in the vicinity of dog kennels at the seaside, urban Kochi, and wooded suburban foothills 7, 000-10, 000 meters from urban Kochi were infected with larvae of Dirofilaria immitis. Five of these were specimens of Culex fatigans, the remaining three were examples of Aedes togoi. Four of the infected C. fatigans were collected at the seaside area, and one was found in urban Kochi. The three infected specimens of Aedes togoi were found in the wooded foothills, the only area where this mosquito was most numerous.

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The authors examined the fleas collected by Mr. T. Miyao and others from small mammals on the Oki Islands in March, 1966. In those fleas, a female specimen of Rhadinopsylla biloba, having a well developed genal comb, which was not previously recorded from the outside of Kyushu, was contained. It was necessary to make a thorough investigation into the flea occurring on the islands. The authors caught small mammals on the Oki Islands during the period from 16 to 21 in December, 1966, and collected fleas from them. The results of the examination of hosts and fleas were as follows : 1) The total of 74 hosts examined were composed of 32 examples of Urotrichus talpoides minutus, 27 of Apodemus speciosus navigator, 14 of A. argentus celatus and 1 of Mus musculus molossinus. 2) U. talpoides minutus was trapped everywhere traps were set, on sunny places and in forests. The two mice of the genus Apodemus were obtained in the almost same areas, however, more careful observation revealed that the habitat of A. argenteus celatus was associated more deeply with the evergreen deciduous forest. 3) The flea fauna of the Oki Islands was not so rich and contained only 3 species of fleas, Palaeopsylla nippon, Neopsylla sasai and R. biloba. 4) P. nippon was found on the majority of the moles examined. R. biloba occurred on the two mice of the genus Apodemus, whereas N. sasai was confined to A. speciosus navigator. 5) R. biloba obtained on the islands had no morphological differences as compared with the specimens from Kyushu. The well developed genal comb of the female specimen, mentioned above, was ascribed to individual variation. 6) On the Oki Islands, R. biloba was distributed in the very low altitude and appeared not to be rare. 7) The record of R. biloba from the islands might serve as a basis for an expectation of its occurrence in the Chugoku district of Honshu.

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The author presented data and discussion on the relationship between the body weights of pupae of house flies, Musca domestica vicina Macq., reared under different population densities of larvae, and number of matured eggs in ovaries of female flies which were emerged from their pupae. A 2 : 1 mixture of wheat bran and powder of fish scrap was used for culture of larvae. Larvae were cultured under different population densities in this medium. Pupae were picked up from the culture medium and their body weights were measured by the torsion balance. The pupae were grouped by their body weight into 6-10, 11-15, 16-20, 21-25 and 26-30mg. On the day of emergence the flies were brought into the cages and were fed by means of cotton ball soaked with milk. Three-to-four-day-old gravid female flies were anesthetized with ethyl ether and the abdomen were fixed in formaldehyde solution. Later, the ovaries were dissected and numbers of matured eggs were counted. The results were as follows. Frequency curve of number of eggs in ovaries showed the normal distribution. The curves moved towards the side of the larger number of eggs when the body weight of pupae were heavier (Fig.1). The average number of eggs in the group of 6-10mg of pupal body weight was 47, and the maximum value was observed in the group of 26-30mg as 156. The values of number of eggs were seen to fall on a straight line (Fig.2). The comparative observation was made by examining the differences between laboratory colonies of vicina-form originated from the wild strain in Osaka and of domestica-form (CSMA) originated from U.S.A. Using pupae of 21-25mg of body weight, the average number of eggs in ovaries observed to be 127 and 135 respectively, and no significant difference could be detected.

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Throughout the year of 1962 flies were collected by the traps with poison bait, containing 0.5% of DDVP and 10% of mollasses in water mixed with 1.2% of isopropyl alcohol, at a hutch where many rabbits were bred located in the center of Kyoto City (A station) and at a farm house in the suburbs of Kyoto City (B station). At B station, survey of flies by trap with fish entrail were carried out to estimate for attractiveness of poison bait to flies at the same time. Trap with poison bait was set successively but changed for new one every five days and flies collected were taken to laboratory. Twenty-four-hour collection using trap with fish entrail was carried out three times at most a month; 28 times in total in a year. At A station, 14, 899 individuals of 12 species were collected by trap with poison bait. Of these species, Fannia canicularis (95.7%) was largest in number, Muscina stabulans (2.1%) was next to it and the other species were rather rare. At B station, 16, 711 individuals of 18 species were collected by trap with poison bait. Of these species, Fannia canicularis (33.0%), Muscina stabulans (32.8%) and Phaenicia cuprina (13.8%) were large in number, and Musca vicina (8.8%) and Aldrichina grahami (4.9%) came next. And 2, 515 individuals of 21 species were collected by trap with fish entrail, of which Aldrichina grahami, Calliphora lata, Sarcophaga peregrina, Phaenicia cuprina and Muscina stabulans were large in number (21.3%, 13.0%, 12.4%, 12.1% and 9.9%, respectively). Seasonal abundance of flies collected are shown in Fig.1, 2 and 3. At A station, Fannia canicularis was collected from late in February to the middle of November and maximum population occurred towards July, and Muscina stabulans was collected from early in March to early September. At B station, Fannia canicularis and Muscina stabulans were collected from mid-March to mid-November by trap with poison bait, and Fannia canicularis was collected at intervals from mid-April to late in October and Muscina stabulans from mid-March to late in November by trap with fish entrail. Both these species were occasionally collected by trap with poison bait even when these were not collected by trap with fish entrail. The results mentioned above indicate that poison bait is more attractive than fish entrail for collecting these species. Phaenicia cuprina, Phaenicia sericata and Sarcophaga peregrina were collected from mid-May to late in October, from early in July to late in October and from mid-March to late in October, respectively, by trap with poison bait. And Phaenicia cuprina and Sarcophaga peregrina were collected for a longer period by trap with fish entrail; from April to December and from April to November, respectively. Aldrichina grahami and Calliphora lata were not collected in summer by both traps and during from November to February. Larger specimens of each species in total were collected by trap with fish entrail than poison bait, in spite of shorter collecting time. The results concerning Calliphoridae and Sarcophagidae mentioned above indicate that during the lower temperature seasons, poison bait is less attractive than fish entrail for flies belonging to these Families. An outstanding feature found in the trap with poison bait is that the number of flesh flies, Sarcophagidae, was less attracted than various species of flies collected. The reason why a few flesh flies were collected may be due to isopropyl alcohol used as fly attractant which might be inadequate to stimulate the olfaction of flesh flies. In the case of collecting flies, a chemical bait containing one odorous material will be brought about uncertain results on fly population.

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1) In order to determine quantitatively the activity of the "Habu" (Trimeresurus flavoviridis), the appearing number of the snakes was observed hourly in the snake pit at Naze Health Center in which 30 snakes were released. In the observations made during the period from 19th to 24th, April 1964, the snakes hid themselves under the dome nests in the daytime and active movement was seen at night from sunset to sunrise with one prominence of activity curve at around 1 a.m. The activity was correlated to the change of the temperature and humidity besides the intensity of illumination. The occurrence of the snake bite was not parallel with this periodicity of the snakes' activity, and the movement of man was considered to be more important factor at the snake bite. 2) The capture rates of the trap boxes were tested in the snake pit. The comparison was made among difference of types of boxes and between presence or absence of a live rat in a trap. The capture rates were different among the types but indifferent to the presence of the rats. The snakes are not sensitive to presence of rats as an attractant.

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To determine the effect of chemosterilants on the mating behavior of house flies, experiments were conducted with male flies sterilized with Hempa. Each pot contained 5 or 10 males and equal females, respectively. Different ratios of sterilized or normal males were used to establish the desired competitive ratio. In two experiments, the percentage of sterile eggs produced by normal females exposed to the males with different ratio of the normal and chemosterilized ones was almost same as, or slightly less than the expected level. It seems that Hempatreated males are sexually as competitive as, or slightly less vigorous than normal males.

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Synergistic actions of S-421 were tested by the Nagasawa's settling mist apparatus, topical application method, abdominal injection method and Leg-Jerk method against the house fly Musca domestica vicina Macqu. The results may be summarized as follows : The knock-down effect of S-421 was high when it was used at high concentrations. The lethal effect of S-421 was stronger than other synergists. The synergistic effect of S-421 evaluated in the abdominal injection method was lower than evaluated by the topical application method. Entomograms of allethrin, pyrethrins, synergists and pyrethroid plus synergists are shown in Fig. 2. It was observed during the test in the Leg-Jerk method that synergistic effect of S-421 increased in the activity of the house fly.

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The effect of a new rodenticide, norbormide, 5-(α-hydroxy-α-2-pyridylbenzyl)-7-(α-2-pyridylbenzyl-idene)-5-norbornene-2, 3-dicarboximide, to some species of rodents was assessed by several lavoratory and field tests. Dose to kill a wild Norway rat, Rattus norvegicus, was found to be 20-30mg/kg by oral administration. But administrations of over 4, 000mg/kg to the mouse, 500mg/kg to Microtus montebelli and 500mg/kg to the cotton rat, Sigmodon hispidus, were not effective. This compound was proved to be selectively toxic to rats. Most of the wild Norway rats died within 1 hour after the oral administration of 30mg/kg of norbormide, and it showed the rapid action of the chemicals. The shyness to the bait with norbormide was not concluded, because, in one case rats seemed to show shyness to the bait and in the other case they seemed not. In field tests using 0.5% norbormide bait in a wooden apartment house (A) and in two poultry farms (B&C), the control was achieved up to the degree of 76.3% in A, 42.5% in B, and 81.7% in C. The number of the dead rodents discovered after the control procedure was 1 of R. rattus and 1 of M. musculus in A, 32 of R. rattus in B and 19 of R. norvegicus in C.

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The 86 individuals of small field mammals collected from 10 stations in Osaka Prefecture were studied and 6 species of laelaptid mites, Laelaps nuttalli, L. jettmari, L. kochi, Echinolaelaps echidninus, Haemolaelaps casalis and 1 undescribed species were found on them. L. jettmari was found in all stations and was dominant species on Apodemus speciosus. L. nuttalli was found in two stations in the field.

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