この研究においてはヤツマタオウバコ (P. japonica forma polystachya) の減数分裂並びに根端細胞において n=18, 2n=36 の染色体数を観察することができた。
この染色体数より本植物は6倍体と推察された。
減数分裂における染色体の行動は正常であり, 時々第二次接合の現象が見られただけであつた。また体細胞における染色体の核型についても研究されたが, この核型は五つの型に分けられることができた。

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Twenty six somatic chromosomes were analysed morphologically. From prometaphase to metaphase, trabants have been frequently observed in two paired chromosomes but unfortunately such figures do not always exhibit to the best advantage.
In B. Evansiana, meiotic chromosomes were first demonstrated by the present study. The secondary association of meiotic chromosome has also been described. The following various types of secondary association were ascertained. (i) 6(2)+1(1), (ii) 5(2)+3(1), (iii) 4(2)+5(1), (iv) 3(2)+7(1), (v) 2(2)+9(1), (vi) 1(2)+11(1) and (vii) 13(1). Six groups of two bivalents and one bivalent was the maximum type.
B. Evansiana may be a secondary balanced allopolyploid based on n=6 and 7 which is the primary basic number.

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Following the 1st report the author injected intravenously lithioncarmin or trypan blue solution into early pregnant mice: and there resulted many abnormal embryos which belong to phenocopies of several hereditary abnormalities. They were: pseudencephaly, distention of the central nervous system, tortuositie and malclosure of the medullary tube, flexion of the medullary tube, short-tail, taillessness, flexed tail, blebs bearing resemblance to the mylencephalic blebs, median harelip associated with pseudencephaly, ectopia cordis associated with a cranial bleb, myelocystomeningocele and severe medullary tube abnormalities associated with abnormally large heart region (pericardium) etc.
These abnormalities manifested themselves regardless of the qualitative differences of the vital staining dyes used. Most of them are abnormalities of the nervous system and fissure formations. It is assumed that some excessive developmental processes may have been produced.
Under the aforesaid abnormalities there are found various conditions belonging to the undermentioned ranks crossing each other: partial flexion of the medullary tube-malclosure or flexion of the medullary tube-tortuosity of the medullary tube< pseudencepaly. distention of the central nervous system.
In the cases of “distention” the coverings of the brains are usually formed small and narrow. The formation of the face region is also retarded, and these embryos usually die during the 11-12th embryonic days, and in some of them the notochord seems to disappear.
It has been reported by Snell et al. in pseudencephaly, and in short-tail or taillessness by Chesley, that distentions of the central nervous system are often observed. From the fact that these abnormal conditions were all obtained in the author's experiments, it may be supposed that there exist a Gloss relationship embryologically-pathologically between them.
On the other hand, the fact that there were also obtained embryos with blisters, like the “myelencephalic blebs”, by the same treatment suggests the existence of some common process in the manifestation of hereditary pseudencephaly, short-tail or taillessness and myelencephalic blebs, which originate from different genes.
The above-mentioned important abnormalities were most frequently observed in the group treated with intravenous injection of 0.1cc. of 1% trypan blue solution on the 8th day (24_h ×8+(12+x)^h) of gestation (6 of 10 pregnant mice had pseudencephalic embryos, and there were obtained in toto 11 psedencephalies, 1 median harelip and 1 ectopia cordis). In the group treated on the 7th day (about 7 1/2 day) of gestation, besides the above-mentioned abnormalities, many severe medullary tube abnormalities associated with large pericardium were especially seen.
Therefore, the critical period of formation of these serious abnormalties, especially of pseudencephaly and other fissure formations, should correctly fall on the 8th day of gestation (presomite or early somite stage), while it was assumed to occur in 9-11th day in the author's previous report.

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The author has succeeded to induce heteroryon artificially on synthetic agar media in two vatrities of Aspergillus Awamori and two mutants of Penicillium chrysogenum Thom Q176 strain.
The heterocaryon between the 5-9 and the N-19 varieties of Aspergillus Awamori was intermidiate between the two parental varieties so far as colour and form of the colony were concerned.
The heterocaryon in Penicillium chrysogenum was induced between two ultra-violet ray mutans; the one, UY-3S strain former jagged colony producing a large amount of yellow substances: sorbicillin and penicillinic acid while the other, UW-1S strain formed round and colourless colony, though colour of spores of both strains were equelly white and quite indistinguishable. The conidia produced by the hetercaryon were green and contained yellow substances just as wild type Penicillium chrysogenum Thom Q 176 does.
Variation of the characters in the heterocaryotic strains was continuous covering the whole range between two parents, the existence of colour substances and the jaggedness of colony, however, being closely associated.
As the number of nuclei in cells of Penicillium usually reaches more than a dozen per cell, it may reasonably assumed that the variation of those chracters in the heterocaryon as stated above results from a combination of different number of nuclei from the two parental strains.

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The three species, N. alata (n=9), N. longiflora (n=10) and N. plumbaginifolia (n=10), were crossed each with N. glauca (n= 12). The crosses N. glauca×N. alata and N. glauca ×N. plumbaginifolia gave some seeds, while no seed was obtained from the cross N. glauca ×N. longiflora. Of the reciprocal crosses, N. alata×N. glauca gave no seed, but N. longiflora ×N. glauca produced some germinating seeds.
The external characters of the hydrids which were produced from the seeds of N. glauca× N. alata and N. glauca×N. plumbaginifolia agreed with Kosteff's description of those of the same hydrids. No report of the hybrid N. longiflora×N. glauca has been published, so far as I know. The features of this hybrid were in agreement with Kostoff's descriptson of those of the hybrid of the reciprocal cross.
All the hybrids mentioned above showed considerable irregularities in meiotic behaviour in PMC's. Polysporous PMC's were. often observed and the hybrids were completely sterile.
At first metaphase in the hybrid N. glauca×N. plumbaginifolia, 0-4 bivalents were counted with the mode at 2_II.
In the hybrid N. glauca×N. alata, 0-7 bivalents were observed, and the most frequent configurations found were 3_II+15_I and 4_II+13_I.
In the hybrid N. longiflora×N glauca, the number of bivalents was 1-6 and the typical configuration of the chromosome complement was 6_II+10_I, though the frequency of this combination was low in proportion among the observed PMC's, since polyvalents ranging from tri- to octa-valents were often found. The chromosomes of this plant showed sticky trend at meiosis, and the divisions were more irregular than those in the above two hybrids. Such remarkable irregularities were not found in the reciprocal cross made by Kostoff, or in the hybrid N. glauca×N. plumbaginifolia according to Kostoff and Goodspeed, in which the paternal parent was taxonomically closely related to N. longiflora.
These irregularities may be due to the difference in the degree of affinity between the maternal plant, N. longiflora, and the chromosomes of the paternal plant, N. glauca, which was probably lower in this direction of the cross than in the reciprocal direction.
The above findings about the three hybrids suggest the presence of a few partially homologous chromosomes between. N. glauca on one side and N. alata, N. plumbaginifolia or N. longiflora on the other. More over, a few chromosomes in diplotene and diakinesis showed end to end junctions, and anaphasic chromosome bridges were always observed.

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