[in Japanese]

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Most of the mutations discovered in Aphiochaeta sp. to date show irregular inheritance. Among these mutations, truncate (t) which appeared spontaneously from wild stock, shows various grades of truncations on wing margins between the 2nd longitudinal vein and the 4th longitudinal vein, ranging all the way from extreme truncate to normal.
When truncate is crossed with wild type, truncate does not appear ordinarily in F₁ but in rare cases it appears in up to a maximum of 8%. F₂ shows a penetrance of from to 20%. In brother and sister matings of truncates a few normals appear, and even after continued selections for more than 50 generations, normals were never completely eliminated.
F₁ expressivity and penetrance of crosses of brother and sister truncates of high expressivity was higher than the F₁ expressivity and penetrance of crosses of brother and sister truncates of low expressivity, and the F₁ of intermediate type gave intermediate results.
Selection of high-expressivity-individuals resulted in producing extreme-expressivity-individuals only, and penetrance become 100%, but at the same time the accompanying decrease in reproductive powers made this line very diff cult to continue.
Selection of low-expressivity-individuals toward the plus and minus direction was effective; this suggests the existence of modifiers.
The truncates among the F₁, F₂ or F₃ individuals of low expressivity obtained from the cross of low expressivity-individual and wild type were crossed successively with the wild of the same brood, and resulted in that the expressivity became concentrated on the selected grade, although the penetrance was variable, being high in some and low in others.
This result also suggests the presence of modifiers.
Sex does not have any bearing on the appearance of truncate character.
The chief factor for truncate is located on one of the autosomes.

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Suzuki has got a mutant which is provided with a supernumerary pair of crescent patterns on the first abdominal segment of the silkworm larva in F₂ of Chinese No. 4 (p) _??_×Hakuryu (p⁺)_??_. This mutant is similar to the supernumerary-crescent silkworms found by Tanaka and Kogure, but differs from those in one point that it has no extraordinary legs. Suzuki called it the “Double-crescented” silkworm.
“.ouble Crescents” segregate Double crescents and the normal in a ratio of 2:1 in sibmating. This ratio may easily be understood by assuming that “Double Crescents” (E^D) is dominant to the normal pattern (p⁺), but is reccessive as to the lethal function.
In crossing of E^D and the “Additional Crescent” (E^Ca) which has one supernumerary pair of Crescent spots on the third abdominal segment, four phenotypes E^D, E^Ca, E^D/E^Ca and p⁺ segregated in a ratio of 2:2:1:2. This is comprehensible by assuming that of E^D, E^Ca and p⁺ are in allelic relations.
While E^D, E^Ca and p⁺ are fertile, E^D/E^Ca is absolutely sterile. The cause of the sterility is due to the deformed sexual organ of the female moth, in which the ovaries are developed normaly, but two oviducts are connected in the proximal ends with each other and formed a single tube, without connected to ovipositor, so that no egg is allowed to come out.

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The natural mutant character, Dirty marking (Di), of the silkworm, Bombyx mori, which has been discovered by Prof. Tanaka in 1939, but not reported about it, is characterized by dark dorsal skin covered by numerous dark spots and lines, just like the intermed ate between the normal and moricaud markings. This character is inherited as dominat, but as recessive for the semi-lunar crescents and star spots to the normal.
From the results of crossing between some marking strains, plain (p), normal (p⁺), striped (p^S), multi-star (ms) and dirty (Di), it is postulated that most strains of the silkworn have generally a gene which forms the special tissue limitted to the places of the semi-lunar crescents and star spots in the larval skin. The author calls it the “Fundamental Crescent” gene.
This gene determines primarily the places of the crescents and stars and forms the special tissue which enables the formation of pigments, p⁺ gene produces pigments secondarily in that special tissue. If no pigment formation takes place, the character results in the plain marking. The multi-star has only a gene which modifies the action of the fundamental crescent gene, but has no pingment forming action. The striped gene does, however, not interact with the fundamental crescent gene at all.

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1. The emerging behavior as a daily rhythmic activity somewhat differ between Drosophila virilis and D. melanogaster. While the number of emerging individuals during 5-8 hours exceeds 50% of the total in the former, it remains always between 20 and 30% in the latter (Tables 1, 2).
2. In D. virilis, no fundamental differences in emerging activity exist between the wild race and the w-race. However, the st-race acts somewhat differently, showing large percentage of emerging individuals during 11-14 hours (Table 1). Cross-experiments, wild×st and st×w, show that this character of st-race behaves as recessive to that of wild race, in accordance with the morphological expression of eye colors in these two races (Tables 3, 4 and 5).
3. In D. melanogaster, no remarkable differences can be found out in the emergense activity between the wild race on the one hand and the w-, st-, vg-and dp-race on the other. However, the se-race behaves somewhat characteristically, i. e., the number of individuals emerging during 2-5 hours is far smaller and that emerging during 11-14 hours is fairly larger than in other races. Cross-experiment, wild×se, shows that this character of the se-mutant behaves rather as dominant to that of the wild race, in spite of recessive nature of se-gene as a determinant of the external morphological expression of eye color (Tables 6, 7 and 8). Flies (wild race) that emerging during 5-8 hours (A series) and 14-23 hours (B series) were successively selected covering 12 generations, but no remarkable differences in the modes of emergence were observed in both series.

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The chromosomes were investigated in male germ cells of Luperodes praeustus Mo tsch. (Chrysomelidae; Coleoptera) with special regards to the structure of the sex chromosomes. The number of chromosomes was determined as 32 in diploid and 16 in haploid (Figs. 1, 2, 8, 10, 11). The male of the present species was found to possess the sex chromosomes of an unequal X-Y pair, a large V-shaped element representing the X and a little smaller J-shaped one the Y. The female was ascertained to be homogametic for the X, since the large V-shaped element is present in a paired condition (Fig. 3). The autosomes are relatively small in size as compared with the X and Y; they appear in the form of curved rod and obscure V, on account of the presence of a remarkable constriction in each.
From the observations through the meiotic prophase, it was pointed out that the sex chromosomes are multiple in structure. The X consists of three components, resulted in the fus on of the original X-element with two autosomes (A and B). The Y chromosome is also of multiple nature, being composed of the a and b elements which are homologous for A and B respectively (Figs. 18-20). It is noticeable that in early prophasic nuclei of meiosis, the autosomal parts of both X and Y take the form of the chromonema thread, while the original X-part remains as the heteropycnotic condensed body (Figs. 4, 5).
In conjugation the Y associates with the autosomal arm of the X. At the first metaphase, the XY complex stands vertical on the equatorial plate, with the autosomal arm of the X parallel to the axis of the spindle (Figs. 9, 12, 13, 14, 15). In the first division, the X and Y separate, and migrate to opposite poles, resulting two sorts of secondary spermatocytes, the X-class and the Y-class (Figs. 10, 11).

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The non-homologous, end-to-end association of chromosomes was observed in male germ cells of the dragonfly, Ictinus rapax (Aeschnidae). It was shown that the end- to-end association of chromosomes is attributable to stickiness of the heterochromatic regions located at the terminal parts of each chromosomes.

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1. In the chloroplast of Selaginella Savatieri the green spirals were confirmed as in the case of S. uncinata. The amoeboid type of the chloroplast-division was detected besides the three types of division, i. e. the ordinary division-type, the longitudinal division-type and the lateral division-type.
In the meristem of S. Savatieri the cell which has only one chloroplast divides after the nuclear division and the thus-formed two daughter cells contain one chloroplast, respectively. Some of these cells which contain one chloroplast remain always to have one chloroplast after successive divisions and remain as the meristematic cells but some of them become to have many chloroplasts which are induced by means of division from the original one.
2. In the shade or the dark place, the structure of the chloroplast which has showed the homogeneous structure changes into the spiral one and the green spirals can be observed clearly. In the chloroplast of S. uncinata the green spirals swell and become to be obscure when treated with 2/5M aqueous solution of NH₄Cl. In the chloroplsts of some plants which have showed homogeneous structure the green spirals become clear when treated with the aqueous solution of acid, alkali or some fixatives. In the chloroplast which shows the green spirals the spiral structure becomes more evidently when left in the shade or dark place.
3. In the cells of Chara sp. which show the active protoplasm-streaming, the chloroplast, sometimes, changes from the homogeneous structure into the spiral one or vice versa.
4. In the chloroplasts of various plants including Pteridophytic ones it is thought the green spirals always exist, but in some cases, the chloroplast shows the homogeneous structure owing to the swelling of the green spirals. In this case, however, the homogeneous structure changes into the spiral one when treated with the reagent which acts to shrink. Therefore, the green spirals are visible or invisible according to its state of swelling or shrinkage.
5. The green spirals are observed in most of the plants, to say nothing of the Pteridophytic ones. The so-called grana is thought to be the optical section, the swollen points, the tightly coiled portion of the green spiral or the products of the photosynthesis. Sometimes, in nature, the grana-structure is observed and it changes reversibly into the homogeneous one through the green-spiral-structure (c. f. Yuasa 1949).
The reticulate, the fibrous, the granulous or the homogeneous structure which has been advocated by the various authors can be explained by the spiral one.
The membraneous structure which has been observed by means of the electron- microscope is though to be induced by the splitting of the green spirals as the polytene threads.

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1. Several species of Lilium belonging Leucolirion and Archelirion groups were studied and their karyotypes were examined.
Leucolirion
Lilium Brownii Brown 2n=24=2 (L₁+L₂+3M₁+2M₂+M₃^s+M₄+M₅^s+M₆+M₇)
L. japonicum Houtt. 2n=24=2 (L₁+L₂+3M₁+2M₂+M₃+M₄+M₅^s+M₆^s+M₇^t)
L. regale Wilson 2n=24=2 (L₁^s+L₂^s+3M₁+2M₂+M₃+M₄^s+M₅^s+M₆+M₇)
L. Makinoi Koidzumi
2n=24=2 (L₁^t+L₂+2M₁+M₁^s+2M₂+M₃^t+M₄+M₅^s+M₆+M₇)
2n=27=2 (L₁^t+L₂+2M₁+M₁^s+2M₂+M₃^t+M₄+M₅^s+M₆+M₇)+2f₁+f₂
L. Alexandrae Wallace 2n=24=2 (L₁+L₂^s+2M₁+M₁^s+2M₂+M₃^t+M₄+M₅+M₆+M₇) Archelirion
L. auratum Lindl. 2n=24=2 (L₁+L₂^ss+2M₁+M₁^s+2M₂+M₃+M₄+M₅+M₆+M₇)
2. In Lilium Makinoi, some individuals have no fragments in the root-tip cells, while others have two or three fragments.
3. The chromosome compliments of these species now studied are quite similar to each other, if we disregard the secondary constriction of each chromosome, but the karyotype of each species are clearly distinguished from each other by the different combinations of the SAT-chromosomes, as in the case of the species treated in our first paper.
4. On the view point of the karyotype, L. Makinoi, L. Alexandrae and L. auratum are closely related to each other, but there are no karyological evidences to support the opinion that L. Alexandrae may be a hybrid between L. Makinoi and L. auratum, as well as the opinion of Wallace that L. Brownii may be a hybrid between L. philippinense and L. Brownii var. colchesteri.

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1) The main results of karyotype analysis in the genus Solanum are summarised as follows:
2) The group so-called night-shade clearly shows an autopolyploid series of the basikaryotype 1L+1L+1M+5M+4S. It is, however, very peculiar that at the reducing division of these polyploid specimens none of the polyvalent chromosomes are found. The facts probably show that an internal change as allopolyploid system occ urred in the genome constitutions.
3) Viewed in point of karyotype aspect, the classification systems of Engler and of Hegi are discussed and the author has concluded that the latter system coincides with our cytological results (cf. Table 1).

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