In the present paper the writer has determined by an analysis of A. fistulosum that two genes are responsible for nonwaxy (nw) and nonviable pale yellow (y) seedlings, which are inherited as recessives to normal. These genes, nw and y, are situated on different chromosomes.

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1. Heritability of three quantitative characters was estimated in two eggplant crosses. The degrees of heritability for the period from seeding to flowering, fruit shape index, and fruit weight were 65-78, 60-75 and 40-60 per cent respectively.
2. Heritability for the fruit shape index and fruit weight estimated by parent-offspring regressions was relatively low, as compared with heritability for them in broad sense, when the variances of F₁ were used for the estimation of the enviromental variances. In connection with this finding, it was concluded that the F₁ variances used as enviromental variances of the segregating generations give too large or too small values, according to the traits.
3. The remarkable differences between the F₂ variances of both crosses were interpreted as due to, effects of genes (polygenes or major gene) governing such traits. This assumption was verified by the frequency distribution in F₂, and its appropriateness was emphasized on the basis of the relationships between the effects of genes and the degree of heritability.
4. The number of effective factors was estimated by the procedure proposed by Mather (4). The estimates were generally low and they were not so reliable, but it was found that the factors having plus or minus effects are probably concentrated within one parent.
5. Various segregants or recombinants were observed in the F₃of the cross Fl×Se, and the range of that segregation was occupying almost the whole range of variation of the cultivated varieties. It may be expected in practical breeding to obtain many new variants from such cross combinations.

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In this study, the karyotype of the somatic chromosomes in Plantago kamtschatica L. was investigated as following; 10 V-shaped chromosomes with submedian and 2 J-shaped ones with the satellite characterized by a secondary constriction.
The karyotype in the present material may be different from the one treated by MacCullagh (1934), and a new instance of this species.
Moreover, the meiotic divisions were found; proceeding regularly. The results are in accord with the finding by Sinoto (1946).

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1. Tetraploids induced from various varieties of Eastern Asia were crossed with certain tetraploid varieties, and fertility, good pollen percentage, plant height and other characters in the F₁ plants were observed. Kamo's castration method was used and F₁s of 121 different variety combinations were obtained.
2. The F₁s were generally higher in fertility than the parental varieties, though different according to the variety combination. Those having high fertilities were to some extent larger in number among variety combinations between the Continental and the Insular groups. And fertility in tetraploid hybrids seemed to correlate slightly negatively with the fertility in the corresponding diploid hybrids.
3. In the percentage of good pollen, though the above-mentioned phenomena were not seen, a number of variety combinations showing high good pollen percentages on tetraploid level were found among those sterile on diploid level. Good pollen percentage was found to correlate with the fertility in seed setting.
4. F₁ plants were generally vigorous in growth, and tended to be higher than the parental varieties. This tencdency seemed to be remarkable in the crosses between the Continental and the Insular groups. And the ratio of the plant height of F₁ to the average of parents was found to correlated with fertility. Considering these phenomena, the rise of fertility in the F₁ seems in a greater part to be due to the complementary effect of genes of parental varieties.

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There were two remarkable types, A and B, of D. auraria, differing in several morphological and oecological characteristics. They also differ in their habitate. Collections and observations were made in an attempt to learn the difference of their habitats between these two types, in Shioya-Mura, near Otaru City, during a period from July to August, 1952. The field of observations ranges in altitude from 30 to 300 meters. The traps, baited with banana or other fermenting fruit, was set at ten places, at an interval of 30m. high, two traps in each place.
It was found that the flies of the A-type were abundant around the places of low altitude, and tended to decrease in number with elevation, while an inverse relation occurred in those of the B-type. They were abundantly obtained around the places of high altitude, 90 to 120 m, high.
Remarkable is that in the population of the B-type the limitation in distribution of the female is rather distinct as compared with that of the male.

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A.M.A. (Acid Methyl Alchol) extracts of the egg and eye pigment components of some egg and eye color mutants of the silkworm, several wild-silkworms and Drosophila melanogaster have been discriminated by paper chromatography using formic acid as a solvent. The results obtained are as follows:
1. Three pigments (orange, red and purple) with Rf values of 0.82, 0.76 and 0.50 are found in the eye of the normal type of the silkworm, and denominated as +chrome-I, +chrome-II and +chrome-III respectively. It has been ascertained from the investigations on the absorption curve and some other biochemical properties that these three pigment components are also found in the egg of normal silkworm and the eye of the wild-silkworm.
2. The compound eyes of w₁, (white-1) and w₂ (white-2) do not contain those three pigments, but the compound eye of w₃ (white-3) contains three pigments as that of normal. The eye of re (red) contains large amounts of +chroine-I, containing no +chrome-II and III, while od (distinct oily) and w₃w^ol strains contain a little three pigments.
3. On the serosa of the silkworm egg, w₁ lacks the three pigments and re contains +chrome-I only as in the eye, and both od and spain (brown color egg) contain small quantities of those three pigments. The eggs of w₂, w₃ and non-hybernating normal, colored by CO₂ treatment, have an orange pigment, which is similar to +chrome-I, though not yet has been identified.
4. As to the appearances of these three pigments in the egg and eye, it is observable that at first +chrome-I is formed, which is followed by the formation of +chrome-II and +chrome-III.
5. As +chrome-I has a peak at 450mμ and it changes to yellow on addition of H₂O₂ and a pink precipitate is formed on reduction with sodium hydrosulfite, so the +chrome-I is closely similar to the brown pigment of Drosophila. But +chrome-II does not show any peak between 300-540mμ, though +chrome-III has a peak at 520mμ, and both pigments become colorless on addition of H₂O₂, showing no change by the treatment of hydrosulfite.
6. From the histological investigation on the pigments in the compound eye, it has been ascertained that re contains most of the red pigment granules in the crystalline part and few in the retinular cell and rhabdomal part, and this feature of the pigment distribution is resembled to that of the eye of normal pupa expected to eclose in four or five days. Although only red pigment granules are distributed in the egg serosa of re, but in the normal egg brownish purple pigment granules are observable showing no existence of red pigment granules, notwithstanding the existence of orange and red pigments distinguishable by paper chromatography. From the above mentioned results, it may be concluded that re is a mutant whether lacking the enzyme or enzyme like substance converting precursor into +chrome-II and III or impossible to form II and III owing to some other unknown factors.

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Results of Goldschmidt ('34) indicated that neutral races of Lymantria dispar had never produced female intersexes in crosses with other races. The present paper deals with the results of gonadal transplantations accomplished between the neutral and strong races.
The 5th instar larvae were used for experiments. Using the larvae of the Noh.-A strain (the strong race from Noheji, Aomori Pref.) as a donor of gonads, ovarian and testicular transplantations were performed with the larvae of the Mi.-A strain (the neutral race from Miyazaki, Kyûshû). The host without gonadectomy received a pair of ovaries or testes from the donor. As shown in Tables 1 and 2, 22.0 per cent of the ovary-transplanted larvae and 28.8 per cent of the testis-transplanted larvae changed into adults.
Close morphological examination revealed that any appreciable change which may be attributed to the effect of the grafted gonads has never observed in the external sex characters of hosts.

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