In this paper I have reported the morphological and biological observations on the larvae of seven species of wireworms belonging to the genus Melanotus ESCHSCHOLTZ, 1829.
The genus Melanotus is readily recognized by the ninth abdominal segment which is flattened at the tip, being usually more or less scalloped posteriorly.
Key to the Melanotus-larvae
1. Body yellowish brown. Second segment of maxillary palpi small, almost as long as wide. Ninth abdominal segment subconical; dorsum convex at anterior half, slightly sloping downward from front to back at posterior half. Median tooth (mto) weakly pointed and forming obtuseangled tip. Larvae not exceeding 25mm. in length.………2
1'. Body reddish brown. Second segment of maxillary palpi large at least 1.4 times as long as wide. Ninth abdominal segment subconical; dors um convex at anterior half, more or less gradually sloping downward from front to back at posterior half. Median tooth (mto) strongly pointed and forming an acute-angled tip. Larvae exceeding 30mm. in length.………3
2. Ninth abdominal segment subconical, about 1.7 times as long as wide; sides of anterior half slightly rounded, and posterior half tapering to a blunt tip. Tergite (tg) punctulate, punctures much denser in posterior half than in anterior half. ………M. fortnumi CANDÈE, 1878
2'. Ninth abdominal segment subconical, about 1.8 times as long as wide; sides of anterior half almost not rounded but straight, and posterior half weakly tapering to a blunt tip. Tergite (tg) uniformly punctulate, punctures a little denser in posterior half than in anteri orhalf. ………M. erythropygus CANDÈZE, 1873
3. Ninth abdominal segment moderately depressed and more or less flattened at posterior half. Median tooth (mto) a little longer than lateral teeth (lto), forming an angle of approximately 60° with lateral teeth (lto). ………4
3'. Ninth abdominal segment strongly depressed at posterior half. Median tooth (mto) about twice as long as lateral teeth (lto), forming an angle of approximately 40° with lateral teeth (lto). Larvae inhabiting in upland forest under bark of decayed coniferous trees.
………M. matsumurai SCHENKLING, 1927
4. Sides of ninth abdominal segment widest near base. Tergite (tg) moderately convex at anterior half, with surface almost uniformly punctulate, punctures less minute in anterior half than in posterior half. ………5
4'. Sides of ninth abdominal segment widest at middle. Tergite (tg) strongly convex at anterior half, with surface densely punctulate, punctures becoming much minuter in anterior half than in posterior half. ………M. legatus CANDÈZE, 1860
5. Lateral teeth (lto) of ninth abdominal segment broad, projecting laterad, forming regular triangle in fresh specimens, with prominent teeth (pto) forming a large nodule respectively.
………M. senilis CANDÈZE, 1865
5'. Lateral teeth (lto) of ninth abdominal segment narrow, sharply pointed towards posteriorly, with prominent teeth (pto) forming small fang-like tooth respectively. ………M. cete CANDÈZE, 1860

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The influences of Warfarin against plasma thromboplastin activity have been analysed, and the following results have been attained.
1. Coagulation time and thromboplastin generation time of Warfarin blood or plasma (coagulation time-prothrombin time) prolonged progressively according to the increase of prothrombin time value but each time above mentioned was reduced significantly by the addition of normal 48 hours serum to Warfarin blood or plasma. Each 48 hours serum incubated at 56°C for 15min., treated with HCl (1 10N), BaSO₄ or Ca₃(PO₄)₂ and plasma treated with Ca₃(PO₄)₂, none of which decreased the coagulation time of Warfarin blood. Furthermore, normal 48 hours serum which was fractionated with 0∼50% of saturated solution of (NH₄)₂SO₄ reduced significantly the coagulation time value of Warfarin blood. Therefore, the reductive effects of normal 48 hours serum to the coagulation time of Warfarin blood seems to be a stable factor contained in serum.
Plasma thromboplastin generation of Warfarin plasma or serum has fallen excessively accrording to the increase of prothrombin time value. The stable factor is an important factor to generate the plasma thromboplastin, and the other plasma thromboplastin factors did not decrease. Therefore, the incompleteness observed in thromboplastin generation of Warfarin plasma or serum was caused by the diminution of plasma thromboplastim complex, which resulted in the decrease of the stable factor.
Similar results were attained in Dicumarol, Neocumaran, Fumarin and Pival blood or serum.
2. Warfarin hardly affected the activity of brain thromboplastin in vitro (measured by normal plasma+5% thromboplastin contained Warfarin+1/40M CaCl₂). Large decreases of brain thromboplastin in mice were observed when the prothrombin time exceeder 300sec.

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The injury of the rice plant csused by the rice stem borer (Chilo suppresslis WALKER) was decreased when the slag containing available silica was manured in soil as stated in the previous papers. This paper deals with the feeding behavior of the larva reared on the silicated rice plant.
The mandible of the larvae fed on the silicated rice plant was diminished remarkably. Thus it seems that the silicated rice plant stem becomes too hard to eat as its food.
The hungry larvae were put in a pettri dish in which a sooted paper was fixed in order to examine their food preferenc, between the silicated rice plant stem and the stem which was cultured in normal or nitrogen rich manure, form their walking traces under condition of darkness. The larvae showed a preference for the normal and the nitrogen manured stem instead of the silicated one.
The water extract of the rice plant stem which was cultured in normal or in nitrogen rich manure was more attractive to the larvae than the silicated one.
It seems that the preference depends not only on the physical properties of the food but also on the chemical properties.

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Soy bean pod borer is one of the most serious insect pests of soy beans in Hokkaido. This species has one brood in a year and the moth appears in August. The percentage of injured seeds caused by this borer shows a great deviation among soy bean varieties and also by years. In this paper authors described the results of their investigation on the yearly deviation of the injuries in Hokkaido.
There was no correlation between the percentages of injured seeds over a period of fifteen years among five localities (Sapporo, Obihiro, Kitami, Teshio and Hayakita). This shows that the factors determining the deviation of injuries are not parallel in these five places.
It was found from the records of the injuries of six soy bean varieties in Sapporo covering the past twenty years, that positive correlation was recognized between the percentages of injured seeds among the varieties where pod-formation periods were near and none among the varieties where pod-formation periods were distant. Then, a negative correlation between the mean temperature of July and the percentage of injured seeds was found in the varieties showing strong response to temperature and none among the varieties showing weak response to temperature. These facts may be understood when the period of moth appearance is accelerated by warmer temperature in July, as the percentage of injured seeds is influenced by the pod-formation period and varieties having an early pod-formation period are infested heavily.
Consequently it follows that the change of the relation between the periods of moth appearance and pod-formation is one of the factors determining the yearly deviation of the injury.
In Obihiro, positive correlation was recognized between mean temperature of September in the preceding year or of August of the current year and the percentage of injured seeds among varieties. This correlation was not observed to be a factor in Sapporo.
In recent two years, 1955∼1956, a remarkable decrease in injuries occured all over Hokkaido. It seems that this decrease in injuries is due to the severe drop in the number of moths.
From the facts above mentioned, it can be said that the factors concerning the yearly deviation of the injury are unlike both in location and in soy bean varieties, or the strength of these factors vary with the location places and the variety of the soy bean.

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This paper deals with the observations on the life-history and biology of two Pamphilid-sawflies, Pamphilius volatilis (SMITH, 1874) and Neurotoma iridescens (ANDRÉ, 1882), pests of cherry-trees in Japan. The observations were made mainly in 1955∼1956 in Sasayama district of Hyogo Prefecture and the data are summarized as follows:
Pamphilius volatilis
The adults appear during the period from the middle of April to the beginning of May. The male lives for a week and the female three weeks. The egg period takes about 11 days, the larval period about 22 days, the prepupal period about 10 months and the pupal period about 17 days.
The female lays her eggs in a group, consisted of about 8 eggs, between 2nd and 4th interveinal parts of the underside of a leaf about 2 meters above the ground.
The larva has 4 moults in both sexes. A group of hatched larvae cooperate with themselves in making a large leaf roll on the leaf-edge by means of their threads, but growing mature they divide into 2 or 3 groups on different leaves. The full grown larva, as soon as it stops to lay threads, falls down to the ground and burrows to considerable depth, about 30cm, where it makes its pupal chamber.
Two species of cherry-trees, Prunus yedoensis MATS. and P. Jamasakura SIEB., are recognized as the food plants, judging from the host-selecting experiments on both adults and larvae.
No parasite could be found, but 5 species of the spiders belonging to the genera Clubiona, Misumena and Argiop, were observed attacking the larvae.
Neurotoma iridescens
The adults emerge a few days later than the former species. The male is active for about 9 days and the female about 26 days. The incubation period is about 2 weeks and the larval period about 25 days. The prepupal stage requires about 10 months and pupal stage about 2 weeks under the ground.
The female lays her eggs in a mass of about 25 eggs on the mid-rib of the underside of a leaf, about 5∼7 meters above the ground.
The larva has 5 moults in male and 6 moults in female. The hatched larvae of a mass move over to the leaf-edge, where they spin a social web feeding together and enlarging it as necessary like a tent caterpillar. They migrate gregariously from one leaf to another or one branch to another by means of their threads. The larva almost always dies when it is separated from the colony. The full grown larva has similar habits to the former species.
Three species of Rosaceae, Prunus yedoensis, P. Jamasakura and Sosbus commixta HEDL., are considered as the food-plants, judging from the host-selecting experiments and field observations.
No parasite could be found in any stages, but three species of the spiders belonging to the genera, Neoscona and Misumena, and a tree-frog, Hyla arborea japonica GUEN. were observed attacking the larvae.

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1. The rate of the passage of water through the isolated cuticle of the silkworm is greater in the intersegmental membranes than in the sclerite regions.
2. The rate of evaporation through the cuticle of both regions decreases gradually with the development during the early stage of the fifth instar, and increases with the development from about 120 hours of age (vigorous feeding stage) to the pupal stage.
3. The rate of evaporation in the direction from endocuticle to epicuticle is about 8 times as great as that in the direction from epicuticle to endocuticle.
4. If the isolated cuticle is either rubbed longer than about 5 minutes with abrasive dust or immersed in warm ether, evaporation is increased enormously, it increases but little with light rubbing or with cold ether.
5. The asymmetrical evaporation disappears by heavy treatment of epicuticle to remove its surface lipids.
6. The evaporation shows a sudden increases if the temperature rises above 57∼58°C (critical temperature).
7. The rate of evaporation through the isolated cuticle is not proportional to the desiccating power of the air. The maximum rate was shown at about 40% R.H., increasing or decreasing with the fall or the rise of humidity.

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A leaf-beetle, Aulacophora fumolaris MOTSCXULSKY, one of the most injurious insects to the water melon and other plants belonging to Cucurbitaceae, produces only one generation in a year, and hibernates in an adult form.
This report deals with seasonal variations of water and lipid contents of an adult beetle throughout the life cycle. The results obtained are as follows.
1. An adult beetle which has emerged in August increases in its body-weight within a month from ca. 26 to ca. 32mg. Simultaneously, it increases in its lipid content from ca. 1.2 to ca. 7mg., being estimated to be from ca. 4 to ca. 22% on the basis of body-weight. On the contrary, the water content of the beetle drops from ca. 70 to ca. 52%, though the absolute amount of water remains unchanged.
2. In September, the new adult beetles begin to migrate from a crop field to a place for hibernation. They are characterized by a well-developed iatbody, and by higher rate of lipid and lower rate of water to the body weight respectively just before and after migration than at any other periods.
3. At first, they flock on the back surface of the leaves of shrubs, and after a month they move to a crevice of a rock or to the base of weeds near the shrubs. We designate the two periods as the pre- and post-hibernating poriod, respectively.
During the pre-hibernating period the beetle decreases in its body-weight from ca. 32 to ca. 30mg., and considerably in its weight of lipid from ca. 7 to ca. 4mg., being estimated to be from ca. 23 to ca. 15%. The water content of the beetle is increased from ca. 51 to ca. 60%, though its absolute amount shows no appreciable fluctuation. The weight of solids other than lipid is decreased a little.
During the post-hibernating period the body-weight of ca. 30mg. is reduced to ca. 25mg. The weight of lipid is also decreased from ca. 4 to ca. 1.7mg.
Solids other than lipid remain constant in their weight, and water content does not change much in its absolute amount. Thus, the percentage both of water and solids other than lipid rises from ca. 58 to ca. 64% and from ca. 27 to ca. 30%, respectively. The content of lipid drops from ca. 15 to ca. 6%.
4. In the later part of March, the beetles migrate from the place for hibernation to the crop field, where they copulate and deposite eggs.
During the period of breeding, the weight of lipid is ca. 1.3mg., being estimated to be ca. 4%, each showing the minimum value of the whole year. The water content increases remarkably either on the basis of absolute amouat or on the basis of percentage, ranging from ca. 17 to 23mg. and from ca. 63 to 67%, respectively.

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This is an account of studies on forecasting the peak date of moth emergence and the population of the moths appears in the first generation, especially in its later period, by knowing the peak of pupation under room condition. The results obtained are as follows:
1. The peak date of moth appearance can be considered from two points; one is the average date of pupation and the other is the date when 50 per cent of total moths have emerged. But these are generally close to each other.
2. It was ascertained that the peak date of pupation of the larvae which were kept under room condition came about 13 days prior to that of moth emergence which was shown by light trap. Therefore, from the relationship above mentioned the peak date of moth appearance can be forecasted.
3. As there is a considerable high correlation (γ=0.81^*∼0.92^**) between the rate of moths appeared in the later period (after June 21) of the first generation which causes the actual damages on the rice plant and the peak date of moth appearance as well as the peak date of pupation, the former can be forecasted by knowing the latter. It may be added that the number of moths appear in the later period will be calculated from the rate of moths captured before June 21.
4. In Ehime Prefecture, these methods seem to be successfully applicable.

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The effect of the photoperiod on the induction and the completion of the diapause in the 4th larval stage was studied at 20∼22°C with the small brown planthopper, Delphacodes striatella FALLÉN.
1. 100 per cent diapause was induced in a short day photoperiod ranging from 8 to 10 hours. The incidence of diapause falls rather abruptly as the duration of illumination shortened or extended over this range, reaching 100 per cent non-diapause in photoperiods of over 14 hours illumination. But in complete darkness the percentage diapause was about 18 per cent.
2. The diapausing larvae never continue to be in the arrest of developement indefinitely in conditions of temperature and photoperiod inducing the diapause. The 4th moulting and emergence occurs ranging from a few days to a few months after the onset of diapause.
3. The diapausing larvae retain their sensitivity to photoperiod. The general trend of the effect of photoperiod on the completion of diapause is similar to that of the induction, the emergence being performed uniformly after 2 to 3 weeks in a long day photoperiod at 20∼22°C.
4. At 30°C the completion of diapause was accelerated though varying with the photoperiod subjected.
5. In spite of these facts which are negative for considering the present type of arrest as the true diapause, some other affirmative attributes are presented. Difficulties for a clear-cut definition of the diapause was discussed.
6. No effect of the night break from 1 to 120 minutes was obtained.

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1. Larvae of rice stem borer, Chilo suppressalis WALKER, show relatively a vigorous gnawing activity of the dried rice-straw in the beginning as well as in the end of the hibernation period except the coldest season during which it decreases to a minimum.
2. The gnawing activity is greatly influenced by the surrounding temperature.
3. The gnawing activity dose not seem to be a sort of “playing instinct”, but has been proved to be the true ingestion of food.
4. The feeding activities in the beginning and the end of hibernation period are considered to serve for the nutritive preparations for entering into or awakening from the winter diapause.
5. From the viewpoint of feeding activity the hibernation of this species seems to be accompanied by true dormancy covering only a part of the apparent hibernation period, i.e., at least in this district of Gifu from the beginning of January to the middle of March.

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[in Japanese]

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