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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The present paper reports the chromosomes of 15 Japanese species of the Pieridae with particular concern to the systematic relationship among them. The numerical and morphological relations here established are referable to Table 1 and Figures 1-32. The author wishes to deal with some cytotaxonomical evidence in the following.
The chromosome number in the studied species of the Pieridae shows a wide range of variation ranging from 17 to 61 in haploid; between these extremes the following numbers, 25, 26, 27, 28, 29, 30, 31 and 54, occur. This is interesting in comparison with the situation cccurring in the Papilionidae, since in the latter the chromosome number is not generally less than 30.
The chromosomes of the butterflies so far reported are uniformly dot-like in form, being rather smooth in outline, while the chromosomes of Leptidea amurensis are characterized by a somewhat angular outline. Further, there occur two “Sammelchromosomen” in this species; probably the formation of the “Sammelchromosomen” can be accounted for on the basis of the union of some dot-like elements.
It is interesting to know that Leptidea morsei and Leptidea sinapis are distinctly different in their chromosome constitution. Leptidea morsei was found to possess 54 dot-like chromosomes (n), while in Leptidea sinapis Lorkovic ('41) reported an individual variation of the chromosome number ranging from 28 to 41, together with the occurrence of the chromosomes of V- and cylinder-like shape. The chromosomes of Leptidea morsei are identical with those of Leptidea morsei major (Lorkovic '50) in general appearance. It is further noticeable that Leptidea amurensis shows the haploid number of 61 which is highest in the Pieridae so far as the observations go.
A chromosomal dimorphism was found to occur in Pieris rapae: there are two groups of animals, one having n, 26 and the other n, 25. The dimorphism is due to the presence of a m-chromosome: the individuals having n, 26 contain a m-chromsome in the haploid set. They are rather frequent in occurrence showing the frequency of 60%.
Pieris melete and P. napi are closely related in many morphological characters, while the chromosomes of these two species differ from each other. The former species is characterized by the basic number of 27 (n), though there is a variation of the chromosome number ranging from 27 to 31 due to the inclusion of the supernumerary chromosomes which vary from 1 to 4. Pieris napi shows a constant number of n, 26.
It was found that the species of Colias and Gonepteryx are characterized by the haploid number of 31 respectively, while those of Aporia show n, 25. No such a constancy in number occur in the species belonging to Leptidea, Eurema, and Pieris.

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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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