The rearing of Anomala cuprea was conducted under the various programs of thermal change to search for the highest survival rate and the shortest duration of developmental period.
The mortality of 1st and 2nd instar larvae was high under cold temperature lower than 15°C. From the feeding stage to the yellow stage of 3rd instar larva, the mortality was low at every temperature examined between 15 and 30°C. During the period from prepupal stage to immature adult, the mortality was low at higher tem-peratures where they had passed through the low temperature (5°C) for more than 40 days from the latter period of 2nd instar to yellow larval stage. In this case the total duration of development was short and its standard deviation was small. The high survival rate during the development was obtained under the changing temperature conditions which were similar to the seasonal change of temperature from summer. Considering these results the most successful program of thermal change to raise this insect was suggested.

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By using homozygous or heterozygous flies of two strains of Drosophila melanogaster, the effect of population density and fluctuating temperature on productivity (the number of progeny produced per female) was investigated. The results show that: 1) There were no differences in productivity between strains, but the productivity of homozygotes was smaller than that of heterozygotes in any condition. 2) The decrease of productivity under the fluctuating temperature was slightly larger in homozygotes than in heterozygotes. 3) Productivity was greatly influenced by population density and temperature, i.e., productivity was smaller under the fluctuating temperature and in the higher density than under the constant temperature and in the lower density. 4) Relative viability of homozygous flies measured by Cy/Pm method was stable for several changed environments. 5) There was a positive correlation between productivity and fecundity which is the number of eggs per female per day. From the results, relations between productivity and environments were discussed.

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Present paper deals with instrumentation of image processing and statistical pattern recognition of plant growth in on-line computer system. The nine images of a cucumber plant were taken through the vidicon camera from vertical angle of 45°, by revolving the plants on the turn table from horizontal angle of 0° to 360° at an interval of 40°. A plant image was digitized with binary notation of 256×256 in image processor by setting a constant slice level of the brightness of the plant. The digitized image was read into CPU and stored in disk memories. The nine digitized images were summed to make a synthesized image which was expressed as the compounded matrix of Eq. (2) . Clear difference in growth was observed in numerical increase and distribution of the elements of the matrix. From calculation of sum (P) of the elements, the quantitative growth was represented by the fuction of P as given by Eq. (3) . Further, in an attempt to design the classifiers for estimation of difference in feature of growth, the vertical position (Jl) of centroid in the compounded matrix was calculated by Eqs. (4) and (5), and relation between Jl and P was ana-lyzed statistically : From covariance analysis, regression equation of normal growth was different from that of succulent growth under 29-33°C as shown in Fig. 6. The 95% confidence limits of each regression equation given by Eq. (6) were used as the discriminant function. As shown in Fig. 7, when coordinate of the point (P_i, Jl_i) belongs to region N, the growth is estimated to be normal. When the point belongs to region S, the growth is estimated to be succulent.
Thus, by image processing of plants, the growth was represented quantitatively as functions of P, and statistical pattern recognition in the coordinate system of P and Jl made it possible to estimate the differences in feature of the growth.

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The effects of the incubation temperature of the embryonic development and the diet composition on the larval growth and the cocoon-shell weight were investigated. The larvae hatched from the eggs at 25°C or 18°C were reared on the diet containing methanol treated cabbage powder (experimental diet) or control diet under LD 16: 8, 25°C.
1) When the newly hatched larvae at 25°C were reared on experimental or control diet for 10 days, there is no difference about the appearance of 2nd instar larvae between these diets.
2) The larvae were reared on the experimental diet during 4th and/or 5th instar under germ-free condition. The larval duration was shortened for 2 or 3 days when egg-incubation temperature was set at 18°C than at 25°C, regardless of the difference of diet composition. However, the cocoon-shell weight was affected by the incubation temperature of eggs. In 25°C incubated group, the larvae fed on experimental diet or control diets (IV, V) produced 326 mg or 445, 320 mg of co-coon-shell weight, respectively. Contrary, at 18°C, the cocoon-shell weight was 272 mg, only 60% of control one.
3) Under conventional condition, the larval duration took longer and the cocoon-shell weight was lighter than under germ-free condition, regardless of the difference of diet composition and of egg-incubation temperature.

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