Nezara is a genus of world-wide distribution and has been represented in Japan by two species, N. antennata SCOTT and N. viridula (LINNÉ), both of which are well known pests of soy been and other various cultivated crops. This genus is considerably related to Glaucias, Palomena and Plautia, which frequently attack fruit-trees and vegetables. There are six species belonging to the above three genera known in Japan. Among those species, Nezara antennata SCOTT and Plautia ståli SCOTT have already been reported on their larval stages by ISHIHARA (1950) and by the author (1956), but Glaucias subpunctatus (WALKER), Plautia splendens DISTANT, Nezara viridula (LINNÉ) and Palomena angulosa (MOTSCHULSKY) have not been studied yet. In the present paper, the developmental stages of the last two species, together with their ecological notes, are described.
The diagnoses of the Genus Nezara
Egg: Cylindrical, with gently curved operculum and vertical wall somewhat thickened in the upper margin. Uniformly pale yellow or pale greenish yellow at an early stage. Chorion white and levigate, without particular structure on surface. Micropylar projections white, rather short, capitate. T-shaped egg-burster light brown or blackish brown, well-chitinized, arms thinly depressed laterally, membraneous appendages mostly transparent except light grayish brown lateral portions or bordered with extremely light grayish tinge infero-laterally. Egg-mass usually consisting of about 50 to 70 eggs which are deposited on the under-surface of host plant leaves, forming a rather regular hexagon.
Larvae: Body not so much depressed. Stigmata placed interior to the connexiva of second to eighth abdominal segments, those on eighth conspicuously smaller than others. The first instar larva bears dorsally a large, round, orange yellow or pale yellowish brown marking extending from vertex to metanotum. The second to fifth instar larvae bear several conspicuous, large or small, round or oblong, orange yellow or white markings adjacent to postero-lateral margins of dorsal plates. A comparatively large, oblong white marking interior to the connexiva of the first and the second abdominal segments and a round white marking interior to each connexivum of the third to the seventh or to the eighth abdominal segments.
Key to the species of the Genus Nezara
1 (2) In he egg before hatching, red eyespots and dark egg-burster visible through operculum. Egg-burster mostly light brown, membraneous appendages translucent except light grayish brown lateral portions. A large round pale yellowish brown marking extending from vertex to metanotum in the first instar larva. The antero-lateral margins of pronotum of the fifth instar larva not so much curved as an arc of circle, posterior angles more or less protruded laterally beyond the anterior angles of mesonotum. ………Nezara antennata SCOTT
2 (1) In the egg before hatching, in addition to eye-spots and egg-burster, a large reddish trapezoid marking clearly visible through operculum. Egg-burster mostly black, membraneous appendages mainly translucent, bordered with extremely light grayish tinge infero-laterally. A large round marking extending from vertex to metanotum of the first instar larva orange yellow. The antero-lateral margins of pronotum of the fifth instar larva strongly curved as an arc of circle, its posterior angles not projecting laterally beyond the anterior angles of mesonotum. ………N. viridula (LINNÉ)
The diagnoses of the Genus Palomena
Egg: Elliptical, upper part of which is more or less bigger than the under part. At an early stage, the eggs are entirely pale greenish, but later, towards the hatch, eye-spots and egg-burster become visible through the chorion. Chorion whitish

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1. In order to clarify the main functions of reducing layers on the integuments of the wireworm, Melanotus caudex LEWIS, comparisons were made on the sensitivity of the reducing layers to ammoniacal silver nitrate between the feeding (spring and autumn) and non-feeding wireworms (summer and winter). Attempts were also made on the effects of pre-treatment with acid solution or hot water on the sensitivity of the reducing layers of the non-feeding wireworms, and on the distribution of the reducing layers in other species of wireworms.
2. The sensitivity of the reducing layers was very high at feeding period, while no reducing reaction was detected at non-feeding period. Moderate sensitivity was found at the period during which the wireworms migrated between surface and deeper layers of top soil. The annual changes in sensitivity are in accord with those in depth of creep in soil (YOSHIDA, 1951).
3. The reducing layers were found to be sensitive during the short periods from late in March to middle in May and from middle in September to late in October.
4. The reducing layers were insensitive when the wireworm crept in deeper layer of top soil for hibernation or estivation. This insensitivity was found to be due to non-reducing substances covering the reducing layers.
5. The non-reducing substances were soluble in acid solution. The sensitivity of the feeding wireworms was not lost by the pre-treatment with hot water or potassium cyanide solution. The non-reducing substances of the dormant wireworms could be removed very quickly by the treatment with acid solution when the wireworms had been treated with hot water.
6. The wireworms collected from deeper layer of top soil in November were cultured at various temperatures, and estimations were made on the days needed for the reducing layers to become sensitive. The sensitivity became apparent on the 50th day at 25°C and 30°C, but never at 15°C and 20°C.
7. In the case of Agrypnus binodulus, in which body water was known to be lost more quickly, the area of the reducing layers was large and their sensitivity was high as compared with Melanotus caudex.
8. The sensitivity of the reducing layers was highest in Agrypnus binodulus and wireworms living in decayed woods such as Alaus berus and Ampedus hypogastricus, was moderate in Melanotus caudex and M. senilis which often caused great damage in upland farm, and was relatively low in Melanotus legatus and M. cete which were found in the soil liable to dry such as field in mountainous region and nursery garden.

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Constructions of the apparatus used in some studies were reviewed and an improved apparatus was constructed for testing the thermopreference of insect which has comparatively large body size and high ability of movement (Figs. 3 and 4).
The apparatus has a large box of insect container (Fig. 3A) which contacts with some brass pipes (B); one end of it is heated by electric coils (C) with bimetal thermostat (D), while another end is cooled with iced water (E). The water melted from ice in the ice box (E) runs in the pipes (B) from cooled end towards the hot end and then drains out (F). By setting up a watertank (G) with a ventilation pipe (H), the brass pipes (B) are filled up with water which is effective to stabilize the temperature in the insect container. Better result should be obtainable when water stream came round from cool end to hot end and then returned back. Instead of making returned stream, some parts of the coils for heating (C) were stretched at the middle portion of the apparatus.
As shown in Fig. 5, the temperature gradient in this apparatus was nearly linear and the temperature at each point was maintained nearly constant for a long time.

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The rice stem maggot, Chlorops oryzae MATSUMURA, has two generations a year in northern Japan and has three in the south. There seems to be local variation in the period of fly emergence both in the two and in the three generation districts. The authors conducted some experiments on growth of larvae and pupal duration, and were able to attain some contributions to the geographical variations in the occurrence of this insect.
The winter hosts of the rice stem maggot with parasitic larvae were sent to Takada from various places. These places are Omagari belonging to the two generation districts, Murakami and Kanose located in border zone of the two and the three generation districts, Matsudai located in mountainuos area of the southern parts of Niigata Prefecture, and Hatano belonging to the three generation districts. The period of the first fly emergence, the duration of larva and the duration of pupa of these materials were compared to those of the Takada's population.
The results obtained are as follows:
1. The larvae of Takada grew most speedy in spring, those of Hatano were secondary speedy, and the growth of larvae of Omagari, Murakami and Matudai was greatly delayed.
2. The period of emergence of the first generation fly of Takada was earliest, and that of Hatano was secondary though delayed about 10 days from the former. In other places that period was more delayed, and in the Matsudai, Murakami and Kanose populations the period from the first to last emergence of the fly was long.
3. The wintering larvae from some places were inoculated into young rice plants and reared in a greenhouse. It was found that the emergence of the fly from Takada was earliest, that from Hatano was secondary, and that from Murakami and Omagari was most delayed.
4. The pupal duration of winter generation of Takada was about 10 days, those of Hatano and Omagari were respectively about 11 and 12 days, and those of Murakami and Kanose were both about 12.5 days.
5. The larval duration of the first brood of Takada was less than thirty days, being shortest in all places examined. It was secondary in Hatano, and longest in Omagari where all the individuals needed more than fifty days to pupate.
The larval durations of Matsudai and Kanose had great variances; some larvae needed only less than twenty days to pupate, but there were the larvae which needed more than fifty days.
6. The larvae of winter generation of Omagari were brought to Takada in autumn of 1956 and reared there throughout 1957. The period of fly emergence of the first brood in 1958 of that population was similar to that of the population brought to Takada in autumn of 1957.
7. It can be stated from these results that there are remarkable geographical variations in growth of the rice stem maggot. The difference between the population of Omagari and those of Takada and Hatano is very significant. It may be concluded that there are two races in the rice stem maggot, the one has three generations in a year and distributes in southern parts of Japan, the other has only two and distributes in the north. But there also seems to be considerable local variations in some provinces of three generation districts.
8. Female flies of the first generation of Takada and male flies of the same generation from Omagari were crossed. The larval durations of the next generation were greatly variable and their variability was similar to that of the Kanose and Matsudai populations.
It is considered from this fact that in the border zone of the two and three generation districts, there are populations which derive from the natural hybridization between the two races.

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When the normal stock of Indian-meal moth, Plodia interpunctella HÜBNER, is reared at about 20°C, all the larvae enter diapause at the fully grown stage and their pupation is interrupted for a long period of time. The diapaused larvae, however, pupate at last and emerge into adults.
On the other hand, by repeated breeding from the moths which emerged relatively early at a temperature of 20°C at which diapause is induced, a new stock is evolved that pupates without any interruption even under this temperature condition.
The present paper is devoted primarily to a study of the effect of high temperature on the incidence of diapause in this non-diapause stock.
In this stock, diapause was induced in fully grown larvae reared at about 20°C when they had been exposed to 30° for some time (2∼8 or 12 days) in the early stages (egg∼2nd instar), but the diapaused larvae pupated at last and emerged into adults like in the normal stock. In this case, however, the larvae of the next generation did not enter diapause so far as they were under the temperature condition of 20°C throughout their developmental stages.
The exposure of individuals to 30°C during one generation (from the egg to the adult stage) had no effect on the induction of diapause in the larvae of the next generation reared at about 20°C, whereas the effect of exposure to 30°C throughout two or more generations remains unknown.

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The authors investigated the numbers of vertabrae of 128 specimens of rats of Muridae and Cricetidae. Mean values of vertebral counts in each species are as follows:
Muridae {Mus musculus: 57.66 Rattus norvegicus: 58.40 Rattus rattus: 63.22 Apodemus speciosus speciosus: 60.22 Apodemus argenteus argenteus: 62.75
Cricetidae {Crethrionomys rufocanus andersoni: 50.00 Eothenomys smithii: 47.50 Microtus montebelli: 48.12
Numbers of vertebrae provided a complete separation of Muridae and Cricetidae groups and gave statistically significant separations of Rattus norvegicus and R. rattus, and Apodemus speciosus speciosus and A. argenteus argenteus.

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Rotenone and its thirty-four derivatives including seventeen new compounds have been examined for their insecticidal toxicities, enzymic inhibition and nervous toxicities, using the azuki bean weevil, the thoracic muscle mitochondria of the horned beetle and the nerve cord of the American cockroach, respectively.
A close correlation existed between in vitro inhibition of glutamic dehydrogenase system, block of nerve conduction and insecticidal activity.
The relation of the chemical structures of rotenone derivatives to their toxicities was discussed. Though it has been reported that the effectiveness of rotenoides is due to the presence of chromano-chromanone ring in the molecule, the present results show that chromano-chromanol ring is also as important.
Trans-configuration at the position 7 and 8 was more toxic than cis-configuration there.

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1. The estimation of SH group in the blood of metamorphosing silkworms, Bombyx mori and Philosamia cynthia ricini, was carried out with the usual fluorometric method of thiamine. In this case, thiamine is to be produced by the reduction of allithiamine (disulfide compound) by SH group in the blood.
2. There occurred difference in the amount of SH group and thiamine in the blood not only between Philosamia and Bombyx but also between the races of Bombyx.
3. A probable existence of some relationship between the metabolisms of SH compound and thiamine is assumed in the blood of metamorphosing stage of these insects.
4. It is suggested that there are at least two types of metabolic pattern of SH compounds in the blood of Philosamia.

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1. Both in the apple grain aphid, Rhopalosiphum prunifoliae, and in the corn aphid, Aphis maidis, the winged offsprings are commonly produced from the unwinged mothers (offsprings born from the unwinged are called “O-UNW”), but very rarely or hardly from the mothers of the same form (offsprings from the winged, “O-W”) even if the offspings are reared under the conditions of overcrowding, starvation, exposure to light and feeding on the stale leaves. On the other hand, in the English grain aphid, Macrosiphum granarium, the winged nymphs are born almost in the same percentage from females of the both forms by the treatments mentioned above.
2. Velocity of development in each instar in relation to environmental temperature was examined in the nymphs derived from both forms of the three species with the assumption that there may be some difference in physiological conditions between the offsprings of both sources in the former two species but not in the last named one. The results are as follows:
a) There is no recognizable difference in the temperature-development relations between O-W and O-UNW in each second, third and fourth instars.
b) In the first instar of O-W of Rhopalosiphum prunifoliae and Aphis maidis, however, the length of the instar is exceedingly greater than in O-UNW and varies strikingly with individuals. In addi tion, it is almost equal in some nymphs in all temperatures ranging from 15°C to 30°C. These are never seen in O-UNW.
c) In Macrosiphum granarium, the effect of temperature upon the first instar is little different between O-W and O-UNW.
3. Some suggestions were presented to explain the phenomena mentioned above on the basis of humoral controls by hormone or hormone-like substance, which is secreted only during the first instar of nymphs and inhibits the growth and differentiation of the wing buds.

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The seasonal trend of the number of rice weevils visiting flowers was investi-gated in Miyazaki from 3rd April to 6th June in 1956.
It is concluded that the rice weevils begin to visit flowers in early April and cease in late May or early June in the southern Kyushu. The number of flowervisiting weevils seems to be determined both by the conditions of flowers and by weather. The surprisingly abundant individuals of weevil visit flowers in farm district.
The rice weevils increase their reproductive rate and seem to elongate their longevity when suck nectar. If the weevils having greater reproductive rate and elongated longevity return to farms after the harvest of crops, the habit of flower-visiting becomes very important from practical standpoint of pest control.
The flower-visiting of the rice weevils in spring is a common phenomenon and is important for a life cycle of the weevils in the southern Kyushu.

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The samller tea tortrix larvae, a leaf feeding Lepidoptera, were reared almost successfully under aseptic conditions on synthetic food media which were slightly modified from the media for the rice stem borer larvae.
The effects of changing dietary levels of the tea leaf powder and dried yeast on larval growth and adult emergence were investigated. Addition of 0.1g (0.9 per cent of dry diet) of the leaf powder showed apparently a promoting effect on the larval growth. The growth of larvae was gradually suppressed by the decreasing amounts of the dried yeast in the media.
The tea leaf powder contains some factor (s) which is considered to be essential for adult emergence. The optimum dietary level of the leaf powder may be more than 10 per cent of dry diet.

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