Flowers of Camellia variety, Somekawa, are variegated. Frequently self-colored red flowers occur, probably owing to mutation of a mutable recessive gene. Co-existence of anthocyanin and leuco-anthocyanin was found in both types of flowers. Estimations of anthocyanin and catechin-like substance including leuco-anthocyanin were carried out spectrophotometrically. The results have shown that leuco-anthocyanin accumulates in the flowers irrespective of anthocyanin formation. Copper enzyme activities in red and variegated flowers compared manometrically, but there was no significant difference between them.

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A genetic study was made on the streptomycin-resistance system of Mycobacterium tuberculosis var. hominis (strains H37 Rv and Aoyama-B) and the following conculusions were obtained.
Survival curves of the organism for streptomycin were discontinuous at two points, at a point between 2 and 5mcg and at another point between 20 and 50mcg under the conditions tested and it has been therefore suggestd that there are three genotypes determining streptomycin-resistance; sensitivity, lower resistance, and higher resistance.
A phenomenon of interference between sensitive cells and resistant mutants as an agent suppressing the growth of resistant mutants as well as a phenomenon of phenotypic resistance have been presented.

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我が国に産するシロチョウ科 (Pieridae) の昆虫8属15種の染色体を観察した。染色体数とその形態は Table I とFigs. 1～32に示した。
1. Pieridae に属するすべての種の精巣は, 外皮の色彩は赤色であり, 形態は完全に結合した球形である。
2. 正常な成熟分裂は成体の精巣においても幼虫, 蛹の時期のものと同様に観察することが出来る。
3. Leptidea amurensis の染色体のみは他の蝶類の染色体と異って多少角ばった形態を示し, また2個の大形ないわゆる “Sammelchromosomen” によって特長づけられる。
4. 日本産の Leptidea morsei と欧州産の Leptidea sinapis との核型は染色体構成に関して非常に異る。前者はn, 54で点状染色体のみからなり, 後者はV形, 棒形の染色体を含むn, 28～41の核型をもち, その間には倍数関係が存在する。
5. Pieris rapae には日本各地にn, 25とn, 26の個体が混在している。その比率は前者が40%, 後者が60%である。n, 25の核型はn, 26の核型からm-chromosome が消失して出来た核型である。
6. Pieris napi はn, 26で, Pieris melete は基本数n, 27に1～4個の過剩染色体が加わり, n, 27～31の染色体数を持ち, 外部形態的に類似しているこの2種も細胞学的には明らかな違いがある。
7. 染色体数とその大きさとの間には密接な関係があり, 染色体数の少い種ほどその染色体は大きい。
8. Pieris 属は P. rapae とP. melete とにおいて核型の多様性がみられ, 細胞学的には相当に不安定な属である。
9. Pieridae は動揺しつつある不安定な Family であるが, 成熟分裂の時期, 精巣の形態及び色彩, 並びに染色体数の諸点から考えて, Family Papilionidae よりは非常に分化した Family と思われる。

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The present article deals with some cytological effects of carzinophilin on the tumor cells of the MTK-sarcoma III, a transplantable rat ascites tumor, with particular regard to the morphological response of the tumor cells to the drug. Intraperitoneal injections at the dose levels of 1000, 2500 and 5000u/Kg were made in tumor-bearing rats on the 3rd day of transplantation.
In the application of a dose tolerated, it was found that carzinophilin attacked initially interphase cells inducing in various ways damage to cells with mitotic distur 1-1 bances. The predominant patterns of response are as follows:
The morphological deformations of nucleoli are most remarkable in affected cells. The nucleoli show irregular thread-like processes or atypical amoeboid protrusions like pseudopodia. The advanced damage is evidenced by the vacuolization of nucleoli. The agglutination of the chromosome threads into several clumps inside the nuclear membrane is also a degenerative change common in affected cells. These cells seem to undergo disintegration without showing mitotic division. Metaphase block is also produced at every dose level. The drug exerts also a destructive effect on the cytoplasm; it induces a blebbing of the cell surface and cytoplasmic swelling, and in a more advanced condition there is a formation of vacuoles in the cytoplasm. The majority of affected cells seems to undergo degeneration. Meanwhile, some of the cells under influence seem to proceed to the metaphase stage, but they are damaged by subsequent mitotic aberrations such as chromosome breakage, bridge formation and anaphase lagging.
Generally the severity of response seems to increase with increased concentration of the drug. The therapeutic effect seems to be expected by separate and repeated applications of the drug at a tolerant dose level, as evidenced by a considerable prolongation of life of tumor-bearing animals.
Upon exposure to carzinophilin, most of the tumor cells were damaged, while certain of them characterized by a small amount of cytoplasm and well-defined compact nuclei remained unaffected by the action of the drug. These persistent unaffected tumor cells constitute the primary source of the subsequent growth of tumor, leading to the reappearance of the tumor in the treated animals. Detailed observations revealed that the chromosome complex of these cells was essentially similar to that of the stemline-cells of this tumor. It is therefore the unaffected tumor stem-cells that participate in the renewed growth of the tumor.

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This lecture^* is a comprehensive summary of all the genetic studies concerned with Drosophila ananassae carried out by the writer and his co-workers since 1931 when the flies were found by chance in Tokyo. It was presented under three major headings, (a) mutants and gene analysis, (b) experimental studies, and (c) studies on population genetics.
Genetic characteristics of this species are as follows:
(1) The fourth chromosome is considered to correspond to the dot chromosome of D. melanogaster or other species of the same group, composed of a bit of euchromatin and a large proportion of heterochromatin, the latter of which occupies major part of the V-shaped body. Further, it is partly identical to some parts of X- and Y-chromosomes, causing such a special allelism of bobbed locus that +bb in Y is allelic with bb in IV and not in X.
(2) In both the second and third chromosomes, except a few dominant genes, all other mutants found belong to the left arms of the chromosomes. The interpretation that the mutability of genes differs in the two arms is preferable.
(3) Power to enhance crossing over was found in the right arm of the second chromosome. The enhancer is able not only to increase the female crossing over somewhat, but also to induce male crossing over. The same kind of enhancer has been known in the third chromosome too.
It is added that this species is a cosmopolitan and domestic species and that the flies frequently carry various types of chromosomal rearrangements in the natural population.

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