1. Total sums of effective temperatures for the completion of whole life cycle (from the beginning of egg period to the first oviposition of the adult) are 650 degree-days for Dacus cucurbitae and 610 for D. dorsalis. Both values are constant in the temperature range between 15° and 30°. Judging from these values the number of generations during the temperate season of a year may be expected to be one or two in Korea, North-China and in the northern half of the mainland of Japan, and two or three in its southern half.
2. Eggs, maggots and pupae all die of cold within 40∼55 days at the constant temperatures below 8°, within 40∼50 days at varying temperatures below 11°, and within 50∼60 days at temperatures falling gradually to 8°. The latter two temperatures are those actually found in the cold season of the year of the temperate climates.
3. Adult flies can live about 100 days at the constant temperatures between 9° and 25°, but cannot survive much longer than 30 days at temperatures below 8°. Under the alternating low temperautres consisting of average daytime and night temperatures of winter in Japan the flies can maintain their natural longevity, if the mean degree is higher than 9° at which the flies display feeding activity. When night temperatures are lower than 8°, especially lower than 0°, their durations of life are exceedingly shorter than those found at the constant temperatures of the same degrees regardless of the daytime temperatures. If the flies are exposed to the winter temperatures of west-southern Japan through passing a series of temperatures falling gradually from autumn to winter starting from the autumn temperatures of Formosa they will not live much longer than 100∼160 days in D. c. or 80∼125 days in D. d., when the exposures begin from September to November and 40∼50 days in the case started from December. Through such gradual exposures the cold-hardiness could be enlarged about 1.5 times in comparison with that found in the sudden one, whereas in all the cases the flies died until the end of February.
Critical temperatures for copulation and oviposition could not be changed by such gradual exposures.
4. Eggs, larvae and pupae will be unable to pass the winter and killed in the period between December and March throughout Japan and its neighbouring countries except southern islands such as Ryukyu, Ogasawara and Izu. Imagines seem to be unable to hibernate in Korea, north-east China, Saghalien, Hokkaido and in all the localities of the mainland of Japan north of Kanto district where the mean night temperatures of winter are below 0°. In the southern half of Japan where average temperatures are higher than 0° at night or higher than 9° during daytime, however, the overwintering may not always be impossible.
5. No larva can maintain life without partaking of food over 30 days at the constant temperatures ranging between 0° and 36°, the longest survival taking place at 10∼12° which are the lowest temperatures of larval feeding activity.
6. Without food, adult flies die within 30 days at the constant temperatures ranging between -6° and 36°, and within 20 days at temperatures below 8°. The longest survival occurs at 10∼12° and the lowest temperature for taking food is 9°.
If the flies are supplied at least with water, the life durations are extended considerably. The maximum survival of 70 days takes place at 14°. In the temperature range lower than 8° the durations are within 20 days. No difference is found in the longevity between at the varying and at the constant temperatures of the same degrees with each other. Also there is no difference in the longevity between individuals supplied with water and completety without food, when the temperatures are higher than 18°.
7. If food is completely unavailable

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In an attempt to breed the rice stem borer during successive generations on synthetic diets, it was found recently that the borer requires ascorbic acid in its food. By addition of this acid into the food medium, the borer can be reared generation to generation.
Two to four hundred milligrams of ascorbic acid per 100g diet seem to be suitable for normal growth of borer. On the diet containing ascorbic acid at such level, weight of larvae, percentage pupation, percentage emergence of normal female moth, number of egg masses laid, and hatchability are all increased. Larvae at the late stages of development require much amount of ascorbic acid as compared with young larvae.
The dry yeast, which is an essential composition of synthetic diet, could not be replaced by known nine B-vitamins. This suggests that the borer requires unknown dietary factors present in the dry yeast, rice bran or rice stem, in addition to the known vitamins.

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1. The egg masses of the rice stem borer moth in the second generation are laied frequently on the under side of rice leaves, as compared with on the upper side of leaves or the leaf sheaths. The frequency of laying the egg masses is the highest on the 3rd leaf and the least on the top and 5th (the lowest) leaves.
2. The newly-hatched larvae from eggs deposited on a leaf, bore into the stem at parts around leaf attachment of respective leaf, particularly of top, 2nd and 3rd leaves. In the case in which larvae hatched on the 4th leaf, however, many larvae enter the stem at the higher position.
3. The borers in the rice stems move gradually downwards. The most active downward movement of the borers occurs with the disparsion and the most larvae matured live in the lowest position of the stem.
4. There are the close relationships between the developmental stages of rice plant and the age distribution of larvae, as well as the inhabiting position of larvae in the stem. In the early-ripening rice plants, the growth stage of larvae advances, and inhabiting position of them is lower in the stem, as compared with those in the late-ripening ones. It is possible to explain the above-mentioned facts by the oviposition preference of the moth and by the higher mortality of larvae which have bored in the stem after the heading.

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For forecasting the appearance of the first generation adult of the peach fruit moth, Carposina niponensis WALSHINGHAM, an attempt was done to determine the termination time of diapause, by means of observating the gonads of larvae in hibernation.
During diapause, testes of larvae, consisting of four testicular chambers, are inactive and remain a definite size, and complete cysts do not yet form in the testes. The male sex-cells in diapausing larvae are in the stage just before the meiosis.
The cyst formation and the meiosis start as soon as testes begin to develop in hibernating larvae after termination of diapause. The formation of spermiodesmens occurs generally just after escape of larvae from their winter cocoon.
Between the larvae reared at Kuroishi-shi (Tsugaru district) and the larvae of Gonohe (the coast of North Pacific Ocean), there are no remarkable differences in both size and development of internal structures of testes, but considerable difference in the duration before the commencement of gonad development by incubation.

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1. If the variance of size of test organisms used in the biological assay experiment of chemicals is large, the dosage applied must be corrected corresponding to their size. When the field collected fishes are used for test or the susceptibilities between two fish species are compared, the correction of dosage corresponding to their size must be needed as almost all fishes grow in the same shape for long time.
2. “Size factor” for equalizing individual differences in body weight can be calculated by the multiple regression equation that the survival time after immersion was determined as the function of dosage and body weight. If the susceptibilities between two fish species are compared by the regression equation expressed the relation between the survival time after immersion and dosage adjusted for differences in weight, weight factor is expected to eliminate for discussion from the factors affecting the experimental result of fish toxicity test.
3. Based on the general idea mentioned above, the comparative test on susceptibility to EI-43, 064 between the goldfish and “Dojo” fish was made by the dipping method. The result has shown that the “Dojo” fish is 5.32 times as susceptible as the goldfish to EI-43, 064. As is seen in the figures of R²'s which are the rates explainable the variance in survival time with body weight and dosage are 69.7 and 31.8% in the goldfish and the “Dojo” fish, respectively. It is considered that the variance of “Dojo” fish was much larger than that of the goldfish from the stand point of biological assay.

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In the present paper, physiological effect of metepa on the hatching of eggs deposited by the treated female×normal male and the normal female×treated male has been compared. The result of statistical analysis by FINNEY'S method on quantitative responses shows that the linear relation exists between the concentration of metepa in logarithms x and the per cent hatching in probits Y. The equations for the case of thetreated female×normal male and for the case of the normal female×treated male were Y=4.2087-2.0008x and Y=4.0391-2.1273x, respectively. From these two regression equations it is concluded that the physiological effect of metepa on hatching of eggs deposited by the treated weevils was not different significantly between the treatment series.

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A strain of the almond moth, Cadra cautella (WALKER), which had been maintained under a constant temperature (30°C) for about eight years, was bred under several combinations of temperature-humidity conditions. Many adult males bred at 25°C had abnormal copulatory organs. Variation of humidity had no influence on the occurrence of such abnormal males.
At a temperature of 25°C, the percentage emergence of males became lower and the occurrence of such abnormal males became frequent. The males seldom emerged below 20°C.
Preimaginal development was remarkably retarded when the 3rd and the 4th instars of males and the 3rd, 4th and 5th instars of females were maintained at the temperature of 20°C for about 5 days. When the 1st and 2nd instars of females were bred under such condition their speed of development was faster than that expected by the law of total effective temperature. Many abnormal males appeared when the 1st and the 3rd instars, prepupa and pupa were bred under such conditions. But no such effect was observed after treatment in egg stage.
From these results it is assumed that the effect of low temperature is different on males and females. Male gonad development and the formation and growth of male copulatory organs are especially influenced.
Why did these abnormalities of development and of sexual character occur at the temperature of 25°C which is nearly optimum for development? The strain used in this experiment has been maintained for many generations at the constant temperature of 30°C and may have become acclimatized to this constant condition, with the result the strain has become sensitive to such slight fluctuation of temperature.
The abnormal forms of the male copulatory organs are as follows: abnormal formations of vinculum and of the valva of one side; degeneration of valva and of aedoeagus; pseudohermaphroditic male with a bursa copulatrix; and a super male having a supernumerary valva.
The ostium bursae of the pseudohermaphroditic male is located between the 8th and 9th sternites. This differs from the prevailing theory of the situation of the ostium. In the pseudohermaphroditic male, one side of the uncus, the same side of the gnathos, the valva of that side, and other associated structures are underdeveloped. The ostium (opening) of the bursa is on this reduced side and is situated on the intersegmental membrane between the vinculum and the 8th abdominal sternite. In the normal female, however, the ostium of the bursa is located on the sternite of the 8th abdominal segment or on the intersegmental area between the 7th and 8th abdominal segments. Therefore the position of the opening of the bursa is not homologous in the intersex and in the normal female. This fact suggests that the morphological position of the opening of the bursa has been interpreted incorrectly for female genitalia of the generalized lepidopterous adult with the exception of Monotrysia. The fundamental position of the opening is on the intersternite area between 8th and 9th abdominal segments. Therefore the ostium must have then advanced into the previous sternite during evolutionary development. Otherwise ovipositor and uncus seem to be homologous as shown in this pseudohermaphroditic male.

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To study the basic mode of action of nematocides, the effects of ethylene dibromide (EDB), cis-1, 3-dichloropropene (cis-D) and 1, 2-dibromo-3-chloropropane (DBCP) on heart pulsation and respiration of American cockroach were investigated.
1. The heart pulsation of EDB injected insect decreased slowly and became irregular and weak. But in insect injected with DBCP or cis-D, the heart pulsation did not change for relatively long period after paralysis, and then suddenly it became irregular and stopped.
2. In insect poisoned by DBCP or cis-D, the oxygen consumption increased with the onset of hyperactivity and slowly decreased with the onset of paralysis. In insect poisoned by EDB, no hyperactivity occurred, but the respiration increased.
3. The oxygen consumption of coxal muscle slices of the cockroach was inhibited 21.5 per cent by 1.8×10^-3M EDB, 18.5 per cent by DBCP and 17.0 per cent by cis-D, respectively.
4. Among the enzymes of the tricarboxylic acid cycle, only the succinic dehydrogenase was inhibited by EDB, but other enzymes were not affected. DBCP and cis-D had no effect on any enzymes of tricarboxylic acid cycle. EDB at final concentration 1×10^-3M inhibited approximately 50 per cent of the succinic dehydrogenase in vitro.
5. The symptom of EDB poisoning was parallel with the succinic dehydrogenase inhibition in vivo, and the enzyme was inhibited about 37 per cent when the roach was paralyzed completely.

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1. The distribution pattern for the size of egg groups laid in leaf blades and sheaths of rice plants was generally very skew, but that in rice seedlings was not so skew.
2. The number of eggs in an egg group deposited in rice seedlings was smaller than that in the blades and sheaths.
3. There were little differences in the size of egg groups between macropterous and brachypterous females.
4. Though fecundity was remarkably influenced by temperature, the size of egg groups was not affected as far as seedlings were used for oviposition plant.
5. It may be difficult to know the fecundity of individuals by examining the number of eggs in an egg group deposited in rice seedlings.

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Prior to the publication of serial reports on population dymanics of the chestnut gall-wasp, Dryocosmus kuriphilus, the life histories of the gall-wasp and its parasites, methods of the study, and the sketch of the permanent survey stations were reported in this paper.
The gall-wasp is a univoltine parthenogenetic insect, of which only female is known. The female lays her eggs into buds of the chestnut tree and the larvae grow in their ball-like galls in the next spring. Causes of mortality influential to the population dynamics are considered to be larval parasitisms and death of adults before the completion of the oviposition. Most parasites have alternative host. Permanent stations are settled at Narashino, Chiba Prefecture, Ôyama, Kanagawa Prefecture, and Tama Zoological Park, Tokyo, of these the first place being recently invaded by the gall-wasp, but the other two being invaded before several years. Routine procedures of sampling shoots and galls were described.

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Amino acid compositions of the honeydew excreted by Ceroplastes pseudoceriferus (GREEN) and of the tea bark on which the scale insect lives, were analysed qualitatively by means of two dimensional paper chromatography.
Fourteen ninhydrin-positive substances were found in the honeydew and were identified as alpha-alanine, arginine, aspartic acid, cystine, glutamic acid, glycine, leucine (and/or isoleucine), lysine, phenylalanine, serine, threonine, tyrosine, valine, and theanine. One ninhydrin positive substance could not be identified.
In the tea bark, 7 to 10 amino acids were found, and identified as follows: alpha-alanine, arginine, aspartic acid, glutamic acid, glutamine, leucine (and/or isoleucine), serine, threonine, valine, and theanine.

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[in Japanese]

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