In the previous paper the author reported on the phase variation in the armyworm Leucania unipuncta (IWAO, 1956), but some aspects of the phenomenon still remained obscure.
An attempt was made in this paper to find the difference in the course of larval development between phases. The larvae were reared at the densities of 1 and 10 individuals per vessel underthe constant temperature of 25°C.
The larvae in both cultures passed through 6 larval instars except one individual having 7 instars in the isolated culture.
Up to the end of the 4th instar no difference is found in the rate of development between the larvae reared in isolation and in crowds, but the larval size in terms of body weight and head width tends to be larger in the latter. During the final two instars the crowded larvae develop more rapidly and at the same time become smaller in size but consume more food than the isolated ones. In high density individual variation decreases in regard to the rate of development. The same is true of the head width until 4th moult, but the variation increases at the later instars.

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1. Population censuses on the wireworm, Melanotus caudex LEWIS, which were limited to the individuals larger than the 2nd-year old, were taken in spring on barley field and in autumn on Chinese cabbage field in 1957.
2. The distribution pattern of the individuals in each section and that beside each plant root in both seasons were in accord with the frequency distribution of Pólya Eggenberger type. χ² test of the fitness was better in the case of plant root than that on the section.
3. To estimate the wireworm population, the counting on the number of worms living beside a plant root is more convenient, because the worms living in a section outside a root of Chinese cabbage are fewer than those living beside a plant root.
4. The explanation of the concentrating nature of the distribution pattern of the wireworm is as follows;
a) the oviposition of the adult insect takes place individually in the soil surrounding the crop plant;
b) the wireworm living near to the soil surface feeds on the crop plant and creeps into it; and
c) the wireworm dwells just under the plant, when it creeps into the deeper layer of top soil.
5. Among the factors opposing the concentrationof the wireworm to crop plant, the scattering of concentrated worms due to soil preparation for wheat (in autumn) and sweet potato (in spring) was taken into consideration. But it did not have a great influence on the dispersion of the wireworm larger than 2nd-year old for the disturbance of soil surface occurred after the wireworm sank into the deeper layer of top soil.
As a natural enemy of the wireworm, a species of Bethylidae was collected. It has any great influence on the distribution of the worm.
6. The frequency distribution in the barley field showed almost the same tendency as in the field of Chinese cabbage.
7. The farms tested had gentle slopes, the west side was higher than the east. Consequently, the density of wireworm was higher at lower side than at the other. It may be due to the special climatic condition at the lower side where no wind blows and it is sunny.
8. In order to find the relations between the difference of population densities and the degree of aggregation of wireworms, the value, S²/x, of each field-section was compared. The values of S²/x proved to be above one, and the degree of aggregation became higher as the density of wireworms increased. The frequency distribution in each section agrees well with that of Pólya Eggberger type, and this fitness is better as the density of a section increases.
9. The number cf wireworm living besides the
root of Chinese cabbage was examined. The
number of collected worms shows the maximum
in the damaged and undamaged leaves in mixed
growth, and decreases at the withered root, the
undamaged root, and the root-lacking place.
10. The value of S²/x at the root-lacking place is below one, shcwing no aggregation of the worm. This comes from the fact that the worms moved to other plants from the Chinese cabbage, which withered due to the damage. The comparatively high aggregation was seen at the undamaged roots.
11. The wireworm density was comparatively low near an ant nest or a mole-hill. At the place of its high density, the only a few larvae of soy bean beetle could be collected, while a few more were collected at the farm-border.
12. When the larvae of the soy bean beetle and the wireworm gather near the plant root on the farm where few plants grow, the former was frequently killed by the latter.
13. It was observed that wireworm fed on the larva of the say bean beetle in a field. The same was observed when wireworms and the larvae of the soy bean beetles were bred in the same pot.

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In this paper I intend to publish bibliographical notes on Scymnus (s. str.) hareja WEISE which has been formerly known as a predacious enemy for some scale insects in Japan, and of this scymnid also to discuss the errorneous or indeterminable specific names used in some Japanese references.
As the food-scales of S. hareja WEISE, 5 species belonging to 3 families have hitherto been recorded. I could confirm in Matsuyama and its vicinities that S. hareja WEISE attacks the following 3 species belonging all to the family Diaspididae, Pseudaulacaspis pentagona TARGIONI (mulberry scale), Unaspsis yanonensis KUWANA (arrow-head scale) and Aspidiotus cryptomeriae KUWANA (round Japanese cedar scale). And, so far as I have investigated, S. hareja WEISE seems to be most abundant on the Citrus-tree, feeding on U. yanonensis KUWANA.
According to my present examination, S. hareja WEISE is distributed in Kyushu, Shikoku and Honshu south of Nikko (Tochigi Pref.), except in the lower temperate districts as Shin'etsu, Hokuriku and San'in (excluding Yamaguchi Pref.). OHTA (1929) described yezoensis, a varietas of this species from Hokkaido and he also reported this species from Formosa, but I have not examined any specimen taken in the ranges from Tohoku district to Hokkaido and from Loo-choo Archipelago to Formosa.
Scymnus (s. str.) seboshii OHTA, 1929, was originally described as a subspecies of S. hareja WEISE and considered later as an aberrant form of the latter by KORSCHEFSKY (1931), MADER (1955), and others. From my comparative study of specimens of the two, typical and aberrant, forms, I came to a conclusion that S. seboshii OHTA is to be separated from S. hareja WEISE as an apparent species, as I have already suggested (1957). S. seboshii OHTA occurs in Mt. Togakushi and Nikko of Honshu and Mt. Ishizuchi of Shikoku, which are the mountainous regions of Japan.
The typical forms of S. hareja WEISE and S. seboshii OHTA can be easily separated from each other by their elytral markings. Although the median spots of both species vary considerably in their size and shape, being connected frequently with the apical markings (Figs. 1 & 2), the spots of the former always retain the black borders along the suture on the elytra even in the specimen with the largest spots. Apart from the coloration of the elytra, I have illustrated the differences between them in the following structure: the punctation of the dorsal surface, especially of the head; the relative length of the eye to the width of frons between the inner margins of eyes, and the anterior margin of the clypeal area (Fig. 3, A & C); the femoral lines and the punctation on the area adjacent to the lines in the first visible segment of venter (Fig. 3, B & D), and the punctation of the other segments of venter; the angle formed by the side margin of pronotum and that of elytra; the male genitalia (Fig. 4) and the female genitalia (Fig. 5).

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In the zone of three generations, the first generation flies of rice stem maggot oviposit on rice seedlings in the nursery bed, the hatched maggots boring near the growing points of host plants, and after feeding on several developing leaves they pupate before the formation of young ears. While, the second generation flies oviposit on the rice plant in near the stage formating young ears, the hatched maggots feed on the developing leaves and young ears, then they pupate.
The author investigated on the larval survival and injury in the first and second generation of the said insect at Takada belonging to the zone of three generations. The results obtained are as follows:
1. The injured leaves are very different between the first and the second generation. In the first generation the maggots can pupate after feeding on three or four leaves. In the second generation they can not pupate after feeding on three or four leaves, but have to feed on the developing young ears to pupate.
2. There are no significant differences among ratioes of stems showing any injured signs to all oviposited stems in either susceptible or resistant varieties to this maggots. Above ratioes are 87% on the average in the first generation but 35% in the second.
3. In the first generation, the varietal differences in the survival percent of larvae are determined in the young stage of larvae. The mortality in the late stage of the larvae which feed and grew enough to show large punctures in two rows on leaf blades is chiefly controlled by factors which affect uniformly on all varieties.
4. In the second generation, major percent of larvae boring into the resistant varieties died too in the young stage. Otherwise, the mortality of larvae which lived to feed on a young ear are likely to be much higher in the early varieties than in the late varieties.
5. It seems to be considered in the second generation that the earlier varieties have more injured ears than those expected from their inherent resistance but the later varieties have fewer injured ears than those expected.
6. From above facts, it is concluded that the percent of individuals surviving to pupal stage in he second generation is lower than in the first geneneration.

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This paper deals with the effect of the water content of rice and the temperature on the velocity of development and the rate of reproduction of eight strains of two species of the rice weevils, Calandra oryzae L., C. sasakii TAKAHASHI. Each strain of C. oryzae was obtained from Japan (JL), Australia (AL), Indonesia (ID) and Missouri in U.S.A. (UM), and that of C. sasakii was from Japan (JS), Australia (AS), Nepal (NE) and Canada (CA).
Generally, the higher the water content in the range from 12.2 to 16.7%, the faster the velocity of development. The influences of water content on the velocity of developments of JL, AL, CA, and NE were greater than these of ID, UM, JS, and AS.
Similar inclination was observed on the rate of reproduction of each strain. There are two types on the influences of water content, one of which is independent on the change of water content, and another is not so. It seems that the former type belongs to the type of storage infestation and the latter that of the cross infestation.
At the temperature of 20, 25, 30°C the days necessary for the development of C. sasakii was slightly longer than that of C. oryzae. Developmental zero point of C. oryzae calculated by theoretical method was comparatively lower than that of C. sasakii without exception, but the totalt effective temperature of C. sasakii was significantly lower. The rate of reproduction of C. oryzae decreased with the increase of temperature between 25°C and 30°C, but increased for C. sasakii.
On C. oryzae, the developmental duration for female was shorter than the male at each temperature. On C. sasakii, however, the male was shorter, except at 30°C. Therefore, there appears to be considerable specific difference between these two rice weevils in regard to effects of temperature.

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The effects of Warfarin on the generation of thrombin and fibrin have been examined with the following results:
1. The normal 48 hour serum and its fractions (each fraction of 0-30, 30-40, 40-50% and their mixtures) which were fractionated with the saturated solution of ammonium sulfate significantly reduced the recalcification time, the thromboplastin time (plasma tested+tissue thromboplastin) and the prothrombin time of the Warfarin plasma, and the prothrombin time of the Warfarin serum. It was found that such reductions of time were caused by the stable factor contained in the normal 48 hour serum. The coagulation times of the normal and the Warfarin plasma were less than the prothrombin time when the thromboplastin complex (plasma treated Ca₃(PO₄)₂+CaCl₂+thromboplastin +48 hour serum or CaCl₂+thromboplastin+48 hour serum) was added.
2. The quantity of prothrombin decreased by about 50% 24 hours after the first administration of Warfarin (0.25mg) and it decreased progressively according to the number of administration. Even though the prothrombin time of the Warfarin plasma was prolonged over 300 sec., 8 to 15% of the prothrombin still remained in the Warfarin plasma.
3. The quantity of prothrombin conversion in the Warfarin blood increased slightly when the normal 48 hour serum was added.
4. The quantity of the stable factcr decreased by 80 to 90% 24 hours after the first administrationof Warfarin (0.25mg) and it disappeared almost completely 24 hours after the second or third administration of Warfarin. The stable factor primarily decreased more significantly than prothrombin.
5. The quantities of the labile factor and prothrombin in the normal plasma showing the minimum value of the prothrombin time were in the ratio of 1:1, but in the Warfarin plasma the rate of prothrombin to the labile factor increased according to the prolongation of the prothrombin time (2:3∼1:4). The ratio between the stable factor and the Warfarin plasma changed to a higher rate of the stable factor quantity according as the increases of the prothrombin time value (1:9∼3:7).
6. In the initial stage of coagulation the consumption of prothrombin in the Warfarin blood was considerably abnormal, but when the normal 48 hour serum was added to the Warfarin blood the consumption became normal.
7. The time that thrombin activity reached the maximum after collecting the Warfarin blood was prolonged according to the increase in the prothrombin time. After the coagulation of blood, the thrombin activity decreased rapidly.
8. The conversion times of prothrombin and fibrinogen and the time of fibrin generation in the Warfarin plasma were prolonged according to the prolongation of the prothrombin time, the prolongation of the prothrombin conversion time being remarkable. However, each time mentioned above was significantly shortened by adding the normal 48 hour serum.
9. The quantity of fibrin in the Warfarin plasma decreased according to the prolongation of the prothrombin time, and even though the normal 48 hour serum was added its quantity did not increase.
10. The time necessary for the disappearance of fibrinogen in the Warfarin serum was prolonged according to the increase in the prothrombin time.
11. The retractility of clot in the Warfarin blood decreased according to the prolongation of the prothrombin time. It did not increase with the addition of the normal 48 hour serum.
12. From the results of the studies up to date, the mechanism of the prolongation of the prothrombin time in the Warfarin plasma can be explained as follows. The prolongation of theprothrombin time in the Warfarin plasma can be attributed to the decrease in the production of thrombin, and to the prolongation of the conversion times of prothrombin and fibrinogen, and of the generation time of fibrin, which is caused by the decrease in prothrombin

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Abraxas miranda is dormant during the hottest season and more or less active in the cooler seasons. In order to analyse the causal relations involved in this seasonal cycle, the effects of photoperiod and temperature upon the incidence of diapause were studied. It was found (i) that Abraxas miranda responds to photoperiod in the larval stage by three different patterns of developmeht in the pupal stage; (a) that the daylength ranging from 14 to 16 hours or longer induces long diapause which is ecologically associated with aestivation; (b) that the daylength ranging from 11 to 13 hours induces short diapause which occurs before winter; (c) that the daylength ranging from 7 to 9 hours prevents diapause of either type; and (ii) that high temperature acts in concert with long photoperiod, and low temperature does so with a short or medium photoperiod. Based on these relationships, the seasonal cycle of Abraxas miranda is causally interpreted.
The author wishes to thank Professor F. Ohmachi of this laboratory for his constant interest and encouragement during the course of this work. His thanks are also due to Dr. T.O. Browning of the University of Adelaide for revising the manuscript and giving invaluable criticism, and to Mr. H. Inoue of Fujisawa for much useful information on the taxonomic relations in the genus Abraxas.

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