Online ISSN : 1348-7019
Print ISSN : 0011-4545
Volume 1 , Issue 2
Showing 1-4 articles out of 4 articles from the selected issue
    1929 Volume 1 Issue 2 Pages 85-87
    Published: 1929
    Released: March 19, 2009
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    1929 Volume 1 Issue 2 Pages 88-108_2
    Published: 1929
    Released: March 19, 2009
    1. Chrom-osmic or chrom-osmic-bichromate mixture is recom-mended for the preservation of the chromosomes of the racoon dog as well as those of other animals.
    2. Two kinds of spermatogonia, the spermatocyte in the early stage and SERTOLI's cell are found on the basement membrane of the seminal tubule of the racoon dog.
    3. Forty-two chromosomes are found in the diploid set and twenty-one in the haploid including X and Y, of which thirteen pairs are atelomitic and eight pairs telomitic. The first division is reductional and the second equational in regard to the tangential rings. In regard to the other tetrads it remains undetermined which division is re-ductional.
    4. The behavior of sex-chromosomes known as heteropycnosis seems to be due to the special colloid-chemical state of the matrix, and probably not to the lack of a homologous partner. MOHR'S hypothesis based upon the orthopteran sex-chromosome can not be applied in the case of vertebrates.
    5. The chromosome formulae of the racoon dog as determined are as follows:
    40+X+Y=42 spermatogonium
    20+XY=21 1st spermatocyte
    20+X=21 2nd spermatocyte a
    20+Y=21 2nd spermatocyte b.
    9. There is found in the racoon dog no chromosomal evidence to determine its genetical relation to the domestic dog, though the two animals resemble each other in their external and osteological charac-teristics, and also in the histological aspect of the testis.
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    1929 Volume 1 Issue 2 Pages 109-191
    Published: 1929
    Released: March 19, 2009
    1. The chromosomes of the male plants of 17 genera, 22 species and 2 varieties of dioecious phanerogams have been investigated. Of these the following 13 forms show each an unequal pair of chromosomes in addition to autosome pairs at the meiotic division in microsporocytes. This unequal pair of chromosomes is assumed to be a sex chromosome complex of an XY-type. Consequently in these forms the male plants are heterogametic with respect to sex. The 13 forms are Salix leucopithecia, S. sachalinensis, S. japonica, S. melanostachys, S. gracilistyla, S. viminalis var. yezonensis Morus bombycis, Cannabis sativa, Datisca cannabina, Daphniphyllum macropodum, Trichosanthes japonica, Hydrilla verlicillata and Trachycarpus excelsus.
    2. In Cudrania triloba, Acer negundo, Trachycarpus excelsus, var. Fortunei and Ginkgo biloba, one unequal pair-like pair is found at the first meiotic metaphase in microsporocytes; but it is not safe to take this for a true unequal pair of chromosomes until a further examination has been made.
    3. One large chromosome pair in Morus and Trachycarpus often divides in two unequal parts at the first meiotic division. The signifi-cance of this particular behaviour, especially in relation to sex determi-nation, is not yet known.
    4. Although many suitable figures of metaphase and anaphase of the first and second meiotic divisions in the male of Spinacia oleracea have been examined, no evidence of the existence of sex chromosomes has been obtained. An examination of the female has still to be undertaken.
    In microsporocytes of Aucuba japonica, 16 chromosomes are found at the first meiotic anaphase. The zygotic numbers of chromosomes in both sexes are the same, being 32. No evidence as to the sex chromo-somes could be obtained in the male plant.
    5. All Salix plants studied, except one form of S. sachalinensis, have 19 as the gametic chromosome number which is a basis in Salicaceae. The meiotic division is quite normal in them.
    One form of S. sachalinensis from Hokkaidoô has ca. 24 chromosomes at the first meiotic metaphase and their behaviour in the meiotic stages is irregular.
    6. Humulus japonicus, growing wild in the vicinity of Tokyo, has a tripartite chromosome in addition to 7 autosomic gemini at the first meiotic division in microsporocytes. At the first meiotic metaphase, the tripartite chromosome divides in such a way that the two end chromosomes go to the one pole, while the middle one goes to the other. Its behaviour is strikingly similar to that of Rumex acetosa. As a result, with respect to chromosomes, two kinds of pollen grains maybe formed. These results confirm that attained by KIHARA.
    7. Humulus lupulus has 10 gametic and 20 zygotic chromosomes. In the first meiotic division of microsporocytes, 16 chromosomes of the 20 form 8 gemini in all, while the 4 remaining chromosomes do not form gemini, but are connected end to end to form a beaded string. This tetrapartite chromosome can be identified in several stages from early diaphase, in the first meiotic division. At metaphase each alternate chromosome of the tetrapartite goes to opposite poles respectively. Thus the daughter nuclei receive an equal number of chromosomes, i.e. 10 respectively. The two middle members of a tetrapartite chromosome are equal in size and larger than the two end ones which differ in size from each other. As a result, two kinds of gametes may be formed, one having a larger amount of chromatin volume than the other. The tetrapartite chromosome may be a sex chromosome complex in H. lupulus, a new type of sex chromosome.
    8. At metaphase of the first meiotic division in the microsporocytes of Xanthoxylum piperitum, 35 chromosomes are counted, one of which is not only the largest
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  • K. YASUI
    1929 Volume 1 Issue 2 Pages 192-215_2
    Published: 1929
    Released: March 19, 2009
    1. Plastid characters in Hosta japonica ASHERS. et GRAEBN. f. albomarginata MAKINO and 9 different kinds of progenies were investigated. The parent albomarginata plant had three different kinds of plastids, namely colorless, yellow and green plastids. Some of the progenies received only one kind of plastid, while others more than one.
    2. The plastid characters show non-Mendelian inheritance in the seedlings from selfed plants.
    3. By the crossing experiments the maternal inheritance of the character in question was determined.
    4. Unlike the case of Funkia ovato (an allied species) studied by STRASBURGER, embryo formation is normal, no apogamy being found. From these facts and the results of crossing experiments with regard to purple spots at the leaf base, the writer concluded that the maternal inneritance of plastid character is gametic.
    5. Especially in the border line between two differently pigmented tissues of mature leaves, two or more different kinds of plastids in one and the same cell were observed in all variegated plants.
    6. The plastids of male parent may or may not be transmitted into the egg cell. If the former be the actual case, the development of such plastids derived from male side must be considered as being prevented from further development in the egg cytoplasm, and the present case of maternal inheritance is due to the inhibitory action of egg cytoplasm, but the various deficient chloroplast characters developed in the progenies are due to the individual characters of plastids themselves and to their irregular distributions into the daughter cells which may happen during the process of the cell division.
    7. The writer considers that the variegated plants here concerned originate from a fertilized egg cell which had two or more different kinds of plastids transmitted from the embryosac mother cell.
    8. There were observed between the neighbouring cells no influence of one kind of plastid upon another, concerning the formation of chlorophyll pigments characteristic to each kind of plastid.
    In concluding the writer wishes to express her sincere thanks to Prof. K. Fujii for his kindly reading through the manuscript.
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