The purpose of this investigation was to study the inheritance of color in variety Aoshima bearing green variegated fruits. The important characters of varieties used in this experiment are described below.
Figure 1 shows the skin color of fruit in variety Aoshima. In order to assume the genotype of Aoshima, the crosses between Aoshima and green fruited variety were chiefly studied, because the genetic behavior of green fruit has already been indicated in the previous paper, and because green variegated fruit in Aoshima seems to be a kind of green fruit. These results may be summarized as follows :
In the cross between green variegated fruit and dark purple fruit (Aoshima×Oserikawa), the F₁ is solid dark purple fruit, thus indicating the recessive nature of green variegated fruit to dark purple fruit. On the contrary, when green variegated fruit is crossed with white (Aoshima×Buko-shiro), green variegation is dominant to white. In the crosses between green variegated fruit and green fruit, there are two distinctly different cases. (a) The F₁ of the cross between Aoshima and Kanto-ao is green variegated fruit, and the F₂ is in the ratio 3 green variegation : 1 green. ConsequentlyG_v gene for green variegation is assumed. (b) Unexpectedly, in the combination between. Aoshima and; Oonasu, the F1 is dark purple fruit (violaceous corolla), and the F₂ is in a trihybrid ratio, when corolla color is taken into account, - namely, in the ratio 36 dark purple fruit (violaceous corolla) : 9 green variegated fruit (violaceous corolla) : 12 green variegated fruit (white corolla) : 3 green fruit (violaceous corolla) : 4 green fruit (white corolla). According to the previous paper, the co-operation_ of three basic genes (C, P, and D) is necessary for the development of purple skin pigments. P gene also controls the purple pigments of the corolla and the other plant organs. G, a gene for, the production of green skin and of light green flesh is assumed in addition to C, P, and D. The probable genotype of Aonasu may be represented by CCppDDGG, and that of Kanto-ao by CCPPddGG.It may therefore be assumed that the result described above is a trihybrid ratio due to three genes (P, D, and G_v), and that the probable genotype of Aoshima is represented by CCPPddGGG_vG_v.

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The present author, in his previous paper, reported that the embryo of the “New Additional Crescent” silkworm, homozygous for the N gene, died in late embryonal stage without showing. any blastokinesis during its embryonal.development.
Since then further studies were made in order to ascertain the anatomical characteristics of the abnormal embryo of both N and Ca strains, with the following results : -
Limits of the multiple effects of the N or Ca gene.
The appendages, bristles, stigmata, and tracheae of the N/N embryo in the 1st to 8th or 9th body segment were found to have the form of the thoracic segments of normal embryo (Figs. 1, 3), whereas the embryo of the Ca/Ca strain had only rudimentary stigmata and tracheae, without any abdominal appendages (Figs. 2, 4) -facts pointing to possibility of numerous interesting studies, particularly in connection with the multiple effects of gene, blastokinesis of the embryo, lethality as the result of abnormal development of embryo, etc.

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The author has described in this report the mode of occurrence, and inheritance of four different chlorina types namely, ch_I, ch_II, ch_III and ch_IV. It is proved that The genes Ch_I and Ch_II, so also Ch_II and Ch_III are respectively complemental for normal chlorophyll development, and behave independently each other.

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1. In the early stage of development the gametophyte, especially the female gametophyte, of flowering plants passes through a multinucleate stage without exception. Non-appearance of the multinucleate stage in the male gametophyte must be due to the suppression of the development of the early stage of the gametophyte generation. In the embryo formation in the gymnosperm plants and the endosperm formation in the angiosperm plants the multinucleate stage also precedes the uninucleate stage. These data show us the common presence of the genes concerning this character in these plants. The common occurrence of the genes in such a large group of plants can not be considered as due to the appearance of these genes in a later stage in their phylogeny, but is more adequate to consider that the genes were inherited through common ancestral form, of these plants :
The regression of the multinucleate stage in the development of the female gametophyte in the flowering plants, from the systematically primitive forms. to the recent ones suggests that the multinucleate stage were probably more developed among ancestral groups.
2. The gametophyte of the flowering plants is of multinucleate and of aquatic type, while the sporophyte is of uninucleate and. of terestorial type. But in their ancestral forms these two generations would have been alike, namely both were aquatic having longer anterior multinucleate, stage and rather shorter uninucleate posterior stage in their lives. In the phylogenetically later stage, in the gametophyte the anterior multinucleate stage is maintained while the posterior uninucleate stage is abridged mostly. On the contrary in the Sporophyte the anterior multinucleate stage is abridged while the posterior uninucleate stage is developed vigorously and highly differentiated; moreover the root formation a most important, and a unique mutant character has appeared in this group. By the development of the root the plant got the capacity of obtaining numerous new materials from the soil, and became possible to grow vigorously as land plant.
3. The parasitic condition of the sporophyte in the early stage of embryo development on the gametophyte had a role for obtaining the terestorial habit of the sporophyte. On the other hand the vigorous growth of the sporophyte on the soil should have led the parasitic habit of the gametophyte on the sporophyte.
4. The multinucleate condition is regarded as the original structure of the protoplast in which the differentiation of uninucleate condition has subsequently been established.

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