(1) The problem of coincidence in crossing-over presents a variety of cases for consideration. In general, coincidence between adjacent regions is lower than I.O. But it often exceeds I.O in the middle region of the V-shaped chromosome, in the translocated chromosomes, or in the ring-formed chromosomes. These facts may be easily accounted for by the assumption of incomplete synapsis or asynapsis.
(2) In the case where non-adjacent regions are codsidered, the gross-coincidence method is more adequate than the usual partial-coincidence method. Thus it has been found that interference is complete to a certain point from the original break, but from that point on, the effect suddenly disappears.
(3) From the study of the various cases, the conclusions reached in my previous papers (1932, 1933) are in the present paper somewhat revised.

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1. This paper deals with the effect of low temperature artificially acted upon the pollen formation in the diploid form of Disporum sessile (n=8).
2. The reduction division occured very irregularly at low temperature and the restitution nuclei and dyad cells were often produced.
3. In a large pollen grain produced at low temperature, the diploid number of chromosomes was counted. They showed, considering from their size and shape, the duplication of the haploid set of chromosomes. From such a pollen grain and a normal egg an autotriploid plant may be expected to occur.
4. Thus an experimental basis was given to the assumption that the autotriploid form (2n=24) of this species existing in the nature may have been formed from the diploid form by the abnormal meiosis caused by exceptionally low temperature often coming in warm season when the normal meiosis goes on.
5. In a pollen grain two extra chromosomes were found together with a normal haploid set. The chromosome categories of the formers were identified according to their size and shape. From such a pollen and a normal egg, a double trisomic plant may be produced.
6. In a pollen grain a normal haploid set and an extra chromosome were observed. The latter was recognized to have arisen by the fragmentation of some longer chromosome at its constriction point.

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The present paper reports the number of chromosomes counted in 45 species of Japanese and European alpine-plants.
From this and the previous paper (Tables 1 and 2), we can see that the alpine-plants which belong to Ranunculaceae are generally diploid and those that belong to Rosaceae are polyploid covering from 4x to 10x.

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We found a new factor in human bloods, which is other than usual factors A, B, M, N and P.
The new factor Q is demonstrable only by a normal pig serum, which contains an anti-Q agglutinin.
The pure anti-Q agglutinin must be prepared by removing a heteroagglutinin, cold agglutinin, group-agglutinins (α', β') which are contained in a normal pig serum.
The heteroagglutinin and cold agglutinin are removed by absorption with human blood cells of O type which have not the Q agglutinogen, and group agglutinins (α' and β') by absorption with Q free human blood cells of A and B type.
The anti-Q agglutinin acts specially on the blood cell which has the Q agglutinogen. The anti-Q agglutinin was found in pig (in rate of 1%) but not in rabbit, cow, horse, dog and hen.
The new factor Q is found in ca 31% of all human blood cells. (Table 1). The presence of Q is dominant against the absence of Q (qq). Hence, genetically three geno-types QQ, Qq and qq will be classified.
We tested the hereditary relation of Q in 103 families. The results will be shown in tables 2-6.

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Es handelt sich um die 40-chromosomigen Zwerge, die in der Nachkom-menschaft der pentaploiden Verbindung T. polonicum×T. spelta aufgetreten sind (vgl. Kihara 1924, Kihara and Wakakuwa 1930). Seit 1922 wurden bis jetzt viererlei verschiedene 40-chromosomige Zwerge gefunden, nämlich D-2g, D-2f, D-2e and D-2d (D=Dinkelgenom; a, b, c, d, e, f, g=die 7 Chromosomen des Dinkelgenoms). Anfangs waren alle diese Zwerge steril. Im Laufe der Jahre traten aber in den Folgegenerationen der drei zuerst gennanten Zwerge zunächst einzelne Individuen auf, die sich von den Schwesterpflanzen der betreffenden reinen Linien durch normalen Wuchs und volle Fertilität in auffallender Weise unterschieden. Später wurden die normalwüchsigen, fertilen Pflanzen immer häufiger, so dass die jüngsten Folgegenerationen dieser Zwerge fast ausschliesslich aus solchen Individuen bestanden and Zwerge nur noch selten zu finden waren. Die Umwandlung fand zuerst bei D-2g und D-2f statt, später auch bei D-2e, während die Zwerglinie D-2d, die erst im J. 1928 aufgetreten ist, bis jetzt unverändert geblieben ist. Über diese Verhältnisse orientieren Tab. 1 und 2. In Tab. 2 sind die Zahlen nur für D-2g und D-2d angegeben; D-2f und D-2e verhielten sich ähnlich wie D-2g.
Die mikroskopische Untersuchung ergab im J. 1934 42 somatische Chromosomen für die normalwüchsig und fertil gewordenen Pflanzen. In demselben Jahre wurden die Reifungsteilungen der PMZ bei den im J. 1933 hergestellten Rückkreuzungsbastarden T. spelta×D-2g and D-2e untersucht.
Es wurden bei beiden Verbindungen 20II+2I gefunden. Aus diesem Befunde ist zu ersehen, dass das neue Chromosom der betreffenden Zwerge nicht das fehlende Element g bzw. e sein kann, da man in diesem Falle 2I Bivalente hätte finden müssen. Ferner liegt es nahe, anzunehmen, dass das neue Chromosom überhaupt nicht zum D-Genom, sondern zu einem der beiden Emmergenome (A oder B) gehört; es dürfte sich um dasjenige Element dieser Genome handeln, das dem Chromosom gebzw. e entspricht (zur Bezeichnung der neuen Chromosomen werden die entsprechenden griechischen Buchstaben, γ und ε verwendet). Das neue Chromosom tritt mit einem der Chromosomenpaare nicht selten zu einem dreigliedrigen Verband zusammen. Dass dabei nur die neuen Chromosomen (γ bzw. ε) in Frage kommen, nicht die von T. spelta gelieferten g bzw. e, kann daraus gefolgert werden, dass bei den Bastarden T. spelta×40-chromosomige Individuuen nie Tripartite festge stellt wurden.
Weitere Untersuchungen über das Zustandekommen der neuen 42-chromosomigen Sippen sind im Gange.

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[in Japanese]

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(1) The present author has succeeded to induce artificially the disturbance of the meiotic division of the pollen mother cells of a pure strain of the balsam plant, by exposing the plant materials to high temperature. The meiotic division of the pollen mother cells of this strain, observed during the summer time at Taihoku, is so unstable that it took place quite normally in some days and behaved very abnormally in other days.
(2) The plant materials were exposed to different, constant temperatures by keeping them in a thermostat for 5 hours. Immediately after the treatment, the mode of meiosis of the pollen mother cells was examined.
(3) The meiosis is practically or quite normal at the temperature below 28°C., while it is irregular at above 30°C. (Table 1). The irregularities become extreem with the rise of temperature, not only in the number of affected pollen mother cells, but also in the degree of irregularity observed in each cell.
(4) The principal types of the abnormality observed in these cases are as follow:-
(a) At the first meiosis: Lagging of a few bivalent chromosomes (Fig. 6); too early (Fig. 1), or too late disjunction of several gemini (Fig. 2); appearance of univalent chromosomes before the metaphase (Fig. 4.7); scattering over of all chromosomes throughout the spindle (Fig. 5), or throughout the cytoplasm (Fig. 7, 17); random disjunction (Fig. 16); etc.
(b) At the second meiosis: Too early splitting (Fig. 7); scattering over of most of the chromosomes throughout the cytoplasm (Fig. 8); wandering of a few chromosomes in the cytoplasm (Fig. 9); formation of a giant equatorial plate consisting of univalent chromosomes (Fig. 10, 11); random splitting (Fig. 11, 12, 13); union of two equatorial plates (Fig. 14); random gathering of the chromosomes in the late anaphase (Fig. 15); etc.
(5) In summarising the results of the experiment, the author has concluded that the unstability of the meoisis of the pollen mother cells of the balsam plant in question must be due to the effect of air temperature, because, this unstability is usually observed at Taihoku during the summer time when the air temperature attains frequently above 30°C. At this temperature, the meiosis of the pollen mother cells of this plant reaches to the critical point resulting abnormality.

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