[in Japanese]

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This paper deals with the inheritance of plant, corolla, and fruit color in the eggplant, with special reference to the development of dark purple fruit pigments. The salient characters of the eggplant varieties used in this experiment are given in Table 1. These results may be summarized as follows:
1. Of seedling color dark purple is dominant over both green and light purple in a monohybrid relation (Table 2, and 4).
2. In the cross between dark purple fruit (violaceous corolla) and green fruit (white corolla), the F₁ is dark purple fruit (violaceous corolla), and the F₂ consists of 3 dark purple fruit (violaceous corolla): 1 green fruit (white corolla) (Table 3). P, a gene for the production of dark purple skin and of violaceous corolla, is assumed, because dark purple fruit is always associated with violaceous corolla and green fruit with white corolla.
3. When dark purple fruit is crossed with white, the F₁ is dark purple, and the F₂ is in the ratio 9 dark purple skin (light green flesh): 3 violet skin (white flesh): 3 green skin (light green flesh): 1 white skin (white flesh) (Table 6). G, a gene for the production of green skin and of light green flesh, is assumed in addition to a gene for the development of dark purple skin (D gene which comes up for discussion later).
4. Dark purple fruit is divided into two groups as regards the influence of the sun; namely in one purple develops under persistant calyx (PUC), while in the other it is confined to the surface that is exteriorly exposed. In the cross between these two groups purple skin under calyx is dominant over light green under calyx in a monohybrid relation (Table 7). It seems that purple skin under calyx is governed by a gene, P_c, in co-operation with P and D gene.
5. In the cross between dark purple fruit with purple under calyx (PUC) and green fruit, the F₁ is PUC, and the F₂ conforms to a dihybrid ratio as recorded in Table 8.
6. In the combination between PUC and white fruit, the former is dominant over the latter in a trihybrid relation (Table 9).
7. The cross between white and green fruited plant consists of two distinctly different cases. (a) The F₁ of the cross between variety Buko-haku and Kanto-ao is green, and the F₂ is in the ratio 3 green: 1 white (Table 10). (b) Unexpectedly, in the cross between Buko-haku and Aonasu, the F₁ is dark purple fruit, and the F₂ is in a typical trihybrid ratio, when corolla color is taken into account (Table 11 and 12).
8. The F₁ of the cross between Kanto-ao and Aonasu which both varieties have green fruits is dark purple, as might be predicted from the result described above, and the F₂ is in a dihybrid ratio, when corolla color is taken into account (Table 13).
9. Flavones as chromogenic substance for the production of anthoyanins are contained in each fruit of Aonasu, Buko-haku, and Kanto-ao, for all of these give the characteristic flavone reaction when fumed with ammonia. Consequently C, a gene for chromogenic substance, is assumed.
10. The results indicate that the co-operation of three basic genes (C, P, and D) is necessary for the development of purple skin pigments, and that P gene also controls the purple pigments of the corolla and the other plant organs (Table 3, 4, 11, 12, and 13).
The probable genotypes of fruit colors in the eggplant are assumed as given in Table 14, and 15.

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Three dwarf types of rice plant, Ebisu (AAbb), Daikoku (aaBB), and Kodaikoku (aabb), differing in the intensity of green colour of leaves, were compared with the normal type Akage (AABB) as to the chlorophyll content. The leaves of those dwarf genotypes contain about 130-150% of the amount of chlorophylls in the normal when the chlorophyll is determined on the basis of the same leaf area, while the less differences were found when it is estimated on the basis of the same weight of fresh leaves. This result was also supported by the comparative studies on the relation between the leaf area and leaf weight in the different types concerned.
Anatomical observations showed that the assimilatory tissues in the leaves of dwarf types are generally about twice as thick as that of normals in the region of the small vascular bundles. In the middle part between two small vascular bundles, however, they are, on account of the abnormal development of the motor cells, rather thinner in dwarfs than in normals.
The palisade tissue of dwarf types, as compared with that of normals, consists of larger cells, but no differences were found as to the size of cells in spongy tissue.
The number of assimilatory cell layers in dwarf types is comparatively large, while the differences in the density of cells in these layers were not proved.
It is concluded that the deep green colour in dwarf types of rice is mainly caused by the large size of palisade cells and the increase in number of the assimilatory cell layers.

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1. A flower character “Suziganezaki” named by the Japanese gardener, which is impossible to open normaly on account of having harder vascular bundles, refers to a gene stiff (s_i) to act as a Mendelian recessive to the normal, as the writer has already reported.
2. The writer's former publication on which a linkage with 23.3 percent in the recombination frequency between contracted (c_t) and side reduced (s_r) was reported, thereby the resulted proposition that s_r is a member of the contracted linkage group, was proved to be in accordance with the further studies that he observed a linkage, its recombination frequency being 26.2 percent, on the data obtained from four crosses.
3. Moreover, the linkage between c_t and s_i which was reported formerly by him, was demonstrated on the total experimental numbers of six crosses, thus obtaining the recombination frequency of 16.4 percent.
4. This fact that interaxial green (i_gI) was found to be linked to s_i with 30.1 percent, and to s_r with 28.2 percent by the writer's studies in the present paper, indicates a high linkage between s_r and s_i, together with the other fact that he found a linkage in a cross, although the recombination frequency could not calculated because of having a few of the experimental numbers, and no double recessive plants.
5. On a cross, a high repulsion was observed between c_t and i_gI.
6. Notwithstanding the fact that Dr. Imai has reported p_r to belong to his duskish linkage group, the writer's studies has proved that p_r links to s_i with 29.6 percent, and also links to i_gI with 42.3 percent in the recombination frequency, therefore it seems to be an undeniable fact that p_r belongs to the contracted linkage group together with duskish (d_k) in Imai's duskish linkage group.
7. The arrangement of these five genes mentioned above, is probably i_gI-c_t-s_i-s_r-p_r on the contracted chromosome.

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Chromosomes in the male germ-cell of two species of dragonflies belonging to the Gomphinae (Aeschnidae) have been studies.
(1) The spermatogonium of Tachopteryx pryeri Mats. contains 17 chromosomes (Fig. 1). The diploid number, 17, is the lowest one so far reported in the dragonfly. A pair of small m-chromosomes and an unpaired X-element can be easily distinguished among them by their shape and size. The m-chromosomes of this species are characterized by their minute size. The primary spermatocyte metaphase shows nine chromosomes composed of eight autosome tetrads and an X-element (Figs. 2-3). In the first division all the chromosomes including the X are divided into equal halves (Fig. 4). In the second division the X, unlike the outsomes, does not divide but goes to one of the two poles entire (Fig. 5). Thus there are obtained two kinds of spermatids, one having the X-element (Fig. 6), the other without it (Fig. 7).
(2) In the primary spermatocyte metaphase of Gomphus hakiensis Selys 12 chromosomes are found including an X-element (Figs. 8-9). There is distinguished no conspicuously small element which can be called an m-chromosome. The X-element, as in all the cases of the dragonfly, divides equationally in the first division (Fig. 10), and runs ahead toward one pole without separation in the second division (Fig. 11), two kinds of spermatids, with and without the X, being produced (Figs. 12-13).

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The present paper deals with the chromosomes in the male germ cells of the following three species of the deep-sea crabs (Decapoda, Reptantia), which were obtained from the Suruga Bay, west of Izu Peninsula, at depths of 200 to 400 meters; Macrocheira kampferi, Nephropsis carpenteri and Nephrops japonicus. The numerical relations of the chromosomes existing in these species of crabs here investigated and morphological features of their chromosomes may be clearly understood from the following table and by reference to the accompanying figures (cf. Figs. 1-14).
It is noteworthy that the tetrads (bivalent chromosomes) observed in the primary spermatocyte of Nephropsis carpenteri do not assume the usual type of compact dumbbell shape widely seen in Decapoda in general, but each consists of well differentiated quadripartite chromatic elements. The fact that about a half of all the tetrads in the closely related species, Nephrops japonicus, possess a similar quadripartite structure, seems to suggest a systematical relationship existing between the two species.
In none of the cases described above, was there any evidence for the presence of the particular chromosomes, either in behaviour or in structure.

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1. The self-pollinated capsules of a stock of Hosta plantaginea Aschers. bear good seeds and aborted ovules in the ratio 1:3 as is shown in the Table 1.
2. The capsules of the same plant when pollinated with the pollen of H. plantaginea Aschers. var. japonica Kikuchi et F. Maekawa bear good seeds and aborted ovules in the ratio 1:1 as is shown in the Table 2.
3. From these data we can assume that Hosta plantaginea Aschers. at least the stock under my observation is a monogenic heterozygous plant of L and l; L denoting a dominant lethal gene causing the partial sterility of this plant, and l its allele, a recessive gene. LL and Ll cause the abortion of the embryo and ll produces a fertile embryo. The gene L does not affect any gametes.
4. Hosta plantaginea Aschers. var. japonica Kikuchi et F. Maekawa which is a self-sterile or at least a later season fertile plant has no L gene in it. When pollinated with the pollen of this plant H. plantaginea Aschers. bears good capsules containing good seeds and aborted ovules in the ratio 1:1.

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