By fixing the purpurea chromosomes with cadmium chloride solution and acetic alcohol, the dicentric system has been made evident in Luzula purpurea.

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With the purpose to study the sexual phase of the gypsy moths from Noheji, Noheji-males were crossed with Sapporo-females; the morphology and the structure of the gonads were observed in the F₁ offspring. The results made possible the conclusion that the Noheji-moths are one of the strongest race.

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It is well known that the number of facets in the Bar-eyed mutant of Drosophila melanogaster varies under different environmental conditions. Recently, Ogaki et al. ('53), Kaji ('54, '55, '56) and Ogaki ('56) showed that facets increased in number when the larvae were raised on media containing various chemicals. In his experiments, Ogaki confirmed that ammonium lactate was the most effective in increasing them in B (bb)-1, B (coiso) and B; e¹¹ strains, a condition as in the wild type being attained in each stock. He also noted that some kinds of chemicals showed marked difference in efficiency among Bar-eyed strains From the results of a series of such experiments, he supposed that in the Bar-eyed mutant the protein and nucleic acid syntheses were more or less hampered, and this might be the reason why only a small number of facets were developed. On the other hand, Kaji has contended that facet-increasing substances must have an amide linkage (-CO•NH-) in their molecular configuration.
In the present work, experiments have been performed with six Bar-eyed mutant strains, namely, B; e¹¹, B; e¹¹ (coiso), B (bb)-1, B(bb)-2, B (coiso) and B w^e strains These stocks differ considerably in their sensitivity to chemicals. Generally speaking, B; e¹¹ strain is the most and B w^e strains is the least sensitive to all the chemicals used with the exception of uracil. These results, which are in essential agreement with a similar conclusion previously arrived at by Ogaki, would suggest that many modifiers probably are contributing to the manifestation of the Bar gene.
Peptone has a striking effect of increasing the facet number of many Bar-eyed strains, so that their compound eye appears almost like that of the wild type. It seems very probable that the substance is utilized as a source of protein synthesis in the eye discs, after it has been decomposed into various amino acids in the larval body. If this is shown to be the case, the above result will substantiate the working hypothesis suggested by Ogaki in his previous paper.

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In order to examine the dependence of the expression of a multilunar gene (L) on a variety of genetical backgrounds, crosses were made between each three multi-lunar strains (H9LRO, H2L and H7L) and several normal strains of different origin.
The expression of the multi-lunar marking was highest in crosses with Tropical and Cantonese races followed by crosses with Chinese, Japanese and European races, decreasing in the mentioned order down to the lowest in crosses with trimoltine races. Such a relationship became more obvious after repeated back-crossing with the same strains.
These results suggest that the expression of a L gene is influenced by several other genes than its normal allele, and that some of these genes may have some relation with voltinism.
It seems likely that the genetical background of such nature is more or less similar within strains belonging to the same local race, while it is not between races of different localities.

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We have already reported that when flies (Drosophila melanogaster, Oregon RS) were successively reared in total darkness. they became more sensitive to illumination or moved more vigorously under light (Mori and Yanagishima, 1959).
In this report we have shown that the flies, which had thus changed their photic reactions in the course of a dark life of 38 generations, maintained the new characters even after 10 to 20 generations under normal daylight conditions. It may be concluded therefore that the change in photic reactions mentioned above has a hereditary basis.
Also, we believe that one of the causes of the somewhat directional long-term variations of the values seen in the tables may be the directional long-term variation of some physiological characters as previously discussed (Mori and others, 1958). Of course, this fact has no influence on the principal conclusion mentioned above.

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