As to the pattern types of the common polymorphic ladybeetle Harmonia axyridis Pallas, there is a distinct geographic gradient (cline) in their relative frequencies at each habitat in Japan, as well as in continental China. A distinct temporal variation (gradient) is found in population samples collected in different years from 1912 through 1965 at Suwa-Tatuno in Nagano Prefecture. These geographic and temporal gradients have probably developed in relation to the local climate, and have their genetic background on the composite and heterotic locus controlling the character.

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The presence or absence of a small elytral ridge in the ladybeetle Harmonia is controlled by a pair of alleles, that for the presence behaving as a simple dominant with a fairly high penetrance. There is a geographic gradient passing through the Japanese island chain in the frequencies of these genes. Significant temporal variations in the frequencies of the genes were observed in samples obtained at Suwa-Tatuno in Nagano Prefecture and at Hukuoka in Kyushu. The rates of temporal changes as well as the geographic gradient, suggest that the pertinent locus is of the heterotic type.

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The rate of water movement of the intestine isolated from the cultured eel in freshwater showed a tendency to an increase in autumn, when the eel in nature migrates to the sea. On the contrary, a tendency towards a decrease was observed in autumn in the amount of sodium ion penetrated from the surrounding seawater into the isolated gills during the incubation. When the eel was transferred from freshwater to seawater for 2 days, the decrease in body weight and increase in plasma sodium and chloride concentrations were the smallest in autumn. The cultured eel in freshwater seems to have acquired the adaptability to seawater in the migratory season, in a similar way as observed in the migrating silver eel in nature.

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A phenotypic 25-year-old male, diagnosed as penoscrotal hypospadias, was found to have an XX sex-chromosome constitution, being chromatin positive in buccal smears and showing drumsticks in some polymorphonuclear leucocytes. Biopsies from right and left testes showed histological pictures characteristic of Klinefelter's syndrome. Some clinical and cytogenetic features were considered in reported XX male cases in comparison with the present case.

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