1. The present report deals with the external characteristics, fertility and the meiosis in PMC's of F₁ (TvCRpHF₁) plants and with the somatic chromosomes of F₂ plants raised from Triticum vulgare (C)-Secale cereale amphiploid (TvCR) and T. persicum-Haynaldia villosa amphiploid (TperH). These F₁ and F₂ plants were obtained in 1962 and 1963 respectively.
2. The number of somatic chromosomes of the trigeneric triple F₁ hybrids (TvCRpHF₁) was found to vary from 46 to 49. 49 corresponds exactly to a sum of the gametic numbers of these original parental plants; T. vulgare (C) 21+T. persicum 14+S. cereale 7+H. villosa 7=49.
3. At the heterotypic metaphase in meiosis of PMC's of F₁ plants 8-16 bivalents were observed in 5 individuals having 2n=46, 10-16 bivalents in 2 individuals having 2n=47, 9-16 bivalents in 10 individuals having 2n=48 and 9-16 bivalents in 3 individuals having 2n=49 (Figs. 4-5). The frequency of the bivalents in one PMC in shown in Table 3. Most of the bivalents consisted of two elements of equal size, and were of a ring-shap conjugated closely, though some of them were stick-shaped, but in some very rare cases, heteromorphic bivalent was observed (Fig. 23). The cases of 14_II in the 2n=47 group and 13_II in other 3 groups appeared to be the mode in F₁ plants respectively (Table 3). It is thought that 14 out of the maximum number 16 of bivalents may be due to autosyndesis of the chromosomes of AB genomes from T. vulgare (C) and T. persicum, and that the other 2 bivalents were raised from autosyndesis of the chromosomes of D genome from T. vulgare (C), considering the results of cytological research on the intergeneric hybrid between T. vulgare (C) and S. cereale by Nakajima 1952 and 1958.
4. Trivalents were observed very frequently, 1-3 in one PMC, in addition to bivalents at the heterotypic metaphase, and tetravalents and pentavalents were rare (Table 4).
5. The many smaller PMC's having lesser chromosomes such as 4_II+26_I (Fig. 19), 1_III+4_II+18_I (Fig. 20), 1_III+5_II+17_I (Fig. 21), 4_II+13_I (Fig. 18), 7_II+21_I (Fig. 23), 1_III+1_II+9_I (Fig. 22), 1_III+7_II+13_I (Fig. 16), 6_II+19_I (Fig. 17) and many others were observed as the anomalous PMC's. It seems that they may be caused by the anomalous division not of PMC but of archesporial cells of these F₁ plants.
6. Most of the 20 TvCRpHF₁ plants, except 3 individuals (No. 12 2n=46, No. 2 2n=48, No. 8 2n=49) which were completely sterile, were fertile, though partially, and 366 grains were obtainedfrom 17 individuals in natural selfing.
7. From 147 out of 267 F₂ seeds from 14 F₁ plants (in October 1963) 58 mature F₂ plants were raised (Table 7). The number of somatic chromosomes of these F₂ plants was found to vary from 40 to 56 (Table 8).

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Somatic chromosomes were studied in Sorex shinto saevus Thomas and Sorex unguiculatus Dobson by means of the tissue culture technique. The diploid chromosome number was 42 in the two species and the karyotype was also very identical with one another.

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Chromosome studies were carried out in tumor cells derived from two cases of gastric carcinomas and from their metastatic lesions. Information was obtained that the stem-line cells with the chromosome pattern characteristic to each case contribute to the growth of both primary and metastatic tumors.

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A temperate phage φ 170 which is dismune to lambda, attaches to the chromosome of Escherichia coli K 12 at a site adjacent to the galactose locus, and can transduce the galactose markers specifically. When a nonlysogenic recipient is used for transduction, a heterogenote (lysogenic syngenote) is isolated. The heterogenote produces a HFT lysate after the induction by UV irradiation. When lambda-lysogenic strains are used as recipients the resulted doubly lysogenic transductants are unstable and segregate Gal^- progenies. Preferential elimination of exogenote and transducing phage is observed in this segregation. The unstable lysogeny is also observed in doubly lysogenic strains of non transductant type. In this case, elimination of prophage is not preferential; the segregants are singly lysogenic of each parental type and a small number of doubly lysogenic and nonlysogenic. The segregation of non lysogenic strain from the unstable doubly lysogenic strain is a useful method for the isolation of nonlysogenic derivatives from various K 12 strains.

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Tryptic digests of chromatographically pure samples of flagellin prepared from a normal flagellar strain and its curly mutant in Salmonella abortus-equi were compared with each other ionophoretically and chromatographically. The two flagellins differ in only one among resultant 35 peptides. The peptides differing between two flagellins have the following characters: 1) they do not contain arginine, histidine and tyrosine; 2) the charge difference are not observed between them; 3) the Rf value of the peptide in curly flagellin is approx. 3.5 times higher than that in normal flagellin.

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The present paper deals with a) a gross comparison of the embryonic stage in CF-1 mice, Sprague Dawley rats and albino rabbits, b) the relationship between the stage at which hypervitaminosis A was administered and the incidence of fetal deaths including embryonic losses as well as of limb and digital malformations, and c) the relationship between various dose levels of hypervitaminosis A and malformation of the extremities in the three species.
Generally, susceptibility expressed by fetal deaths, including embryonic losses, seems to be the highest in the rabbit, next in the mouse, and the lowest in the rat, while susceptibility of limb buds and hand or foot plates to the teratogenic action of hypervitaminosis A seems to be the highest in the mouse, next in the rat and the lowest in the rabbit.

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From morphological, physiological and cytogenetical studies of ten different interspecific tetraploid and hexaploid hybrids among five Japanese, two Nepalese and an American species of Agropyron, the following results were obtained.
1. Most of the interspecific F₁ plants are vigorous and in general the characters in F₁ are either intermediate between the parents or superior to those of the parents.
2. Complete pollen sterility and high seed sterility were the rule in all combinations examined.
3. From chromosome pairing in F₁ hybrids, it is concluded that (1) two genomes of Japanese tetraploid species, Ag. ciliare and Ag. yezoense, are very similar, (2) two Japanese hexaploid species, Ag. humidum and Ag. tsukushiense, have quite identical genomes, (3) genomes of a Nepalese tetraploid species, Ag. semicostatum, are closely related to those found in Japanese tetraploid species, and (4) an American tetraploid species, Ag. trachycaulum, possesses genomes distantly related to those of Japanese tetraploid species.

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