Eggs of Coccophora Langsdorfii were centrifuged respectively before fertilization and after determination of the morphological polarity towards various directions at 400 to 25, 000 times gravity. As a result, the following was revealed. (1) The limit of centrifugal force necessary for stratification of the endoplasmic elements lay between 2, 200 and 2, 700 times gravity regardless of the developmental stage. (2) No difference was perceived in the velocity of stratification among directions, basal, apical and lateral, towards which the egg was centrifuged. The velocities of redistribution of the stratified elements also could not be distinguished with directions in which they were centrifuged. (3) From these facts, it is not considered that there is a polar cyto-skeletal system in the endoplasm of fucoid eggs.
1) Sub-optimal concentrations of indole-3-acetic acid (IAA) added to the optimal concentration of 1:4-dihydronaphthoic acid-1 (1:4-H2-NcA) increased the elongation of etiolated pea stem sections, and the optimal concentration of IAA added to it did not cause the supra-optimal depression effect. The same was true when IAA was added to naphthaleneacetic acid (NAA). 2) Sub-optimal concentrations of NAA added to the optimal concentration of 1:4-H2-NcA did not increase the elongation, and high concentrations of NAA added to it caused the depression effect. 3) 3-Chloro- and 4-chlorophenoxy-isobutyric acids were antagonistic to IAA but not to 1:4-H2-NcA and NAA. 4) All results are consistent with the assumption that 1:4-H2-NcA and NAA act on the same reaction site, but that IAA acts on a different site.
Induction of sexuality in Chlamydomonas moewusii var. rotunda, which was used as C. sp. 24 in the previous experiment, was dependent on the concentration of assimilable N in the medium (Tsubo, 19562). The sexual activity of cells dedifferentiated also in the presence of assimilable N. Since it was supposed that the inhibition of mating reaction by N would be due not only to the nutritional, but also to the ionic interference, the experiments were performed to see the effect of each ion used in the culture medium on the sexual reproduction of this alga. Bivalent cations such as Ca++ and Mg++ promoted, but monovalent cations such as K+ or Na+ inhibited the mating reaction. On the other hand, K+, Na+ and Mg++, but not Ca++ promoted the preceding step, induction of sexuality. NH4+ and NO3- inhibited both of these processes. Furthermore, it was noticed that none of these ions was indispensable, but a physiological balance in the medium produced by the ionic interference, e.g. with K+ and Ca++, or K+ and Mg++, was important for the accomplishment of sexual reproduction.
When I reported about the morphology of female cones of Taxodiaceae, Metasequoia trees in Japan were so young that I could not get cones of various maturity. However, last year Dr. Hideo Takada kindly gave me these cones, and I made observation on them. The result is that the development of female cones of Metasequoia was the same as in the case with Sequoia sempervirens (Fig. 1), i.e. the bract and the ovuliferous scale can not be distinguished from each other on the female cone. The ovuliferous scale develops remarkably during mature time of the cone. The form of mature cone-scale is bilabial, whose upper lip implies the ovuliferous scale and lower lip consists of ovuliferous scale and bract. The ovuliferous scale and bract can not be distinguished from each other externally in the adult cone. These results suggested that Metasequoia is more intimately related to Sequoia and Sequoiadendron than to other members of Taxodiaceae. The top and the next pairs of cataphylls on the peduncle which showed no elongation of the internode attach to the base of the mature cone (Fig. 2, A). Mostly the top pair is covered with the recurved lower cone-scale (Fig. 2, C) and occasionally only the top pair adheres to the cone (Fig. 2, B).
Observation of morphological changes was made in Micrococcus glutamicus and other glutamic acid-producing organisms cultivated in the synthetic media containing Na-citrate or Na-malate. Elongated and branched cells were formed under such condition. 1. Addition of Na-citrate In a medium containing 3% of Na-citrate, formation of branched cells was rarely observed. And in the medium containing 4 to 5% of Na-citrate, branching of cells appeared markedly. However, shortening of branches and simultaneous change of cell shape into so-called “bifid bacteria form” occurred when the concentration of Na-citrate increased up to 6% or more. 2. Addition of Na-malate Branches were formed when cells were cultivated in the synthetic medium containing 7% or more of Na-malate. In this case, however, majority of cells were lysed. “Bifid bacteria form” was not observed in the Na-malate medium. By Webb's cell wall staining method, it was observed that elongated or branched cells were always of multicellular form with several or more septa. Spiral, large, point-like, and symmetrical nuclei were observed in elongated cells by HCl-Giemsa nuclear staining method. As the branching of a cell proceeded, the nucleus of the cell was divided into two daughter nuclei, then, one of which moved into the branch.
On the basis of the experiments on pigment formation in several strains obtained from Penicillium islandicum Sopp, by UV-irradiation, biosynthetic interrelationships of the pigment components may be summarized as follows: 1) The strains obtained by irradiation are not mutants caused by gene mutation, but defective strains due to cytoplasmic change in irradiated spores. 2) In the strain NRRL 1175, the pathway leading to skyrin, oxyskyrin and skyrinol is found to be quite stable against UV-irradiation, and the loss or recovery of individual pigments has been achieved step by step during successive culture. Therefore, these 3 pigments are involved in the main pathway which proceeds according to the following fashion: skyrin→oxyskyrin→skyrinol. However, chrysophanol, emodin and flavoskyrin are unstable, and the appearance or disappearance of these pigments takes place independently of each other. The biosynthetic route of the pigments in the strain NRRL 1175 is shown in Fig. 2 in the text. 3) In some defective strains obtained from the strain NRRL 1036, a faint new pigment spot comes into appearance in place of spot-j on the chromatogram only after disappearance of the latter pigment. This new pigment was identified as skyrinol by paper chromatography (Table 5). Thus, it is likely that skyrinol is also present in the strain NRRL 1036 probably being masked by preponderant spot-j on the chromatogram. Therefore, the route, skyrin→ oxyskyrin→skyrinol, is the main pathway also in this strain. Islandicin and iridoskyrin are formed from a common precursor in a competitive manner. The interrelationship between rubroskyrin and luteoskyrin is quite similar to that between islandicin and iridoskyrin. In view of these experimental findings, a scheme of pigment synthesis in the strain NRRL 1036 is illustrated in Fig. 3 in the text. 4) Erythroskyrin stands outside the biosynthetic route of anthraquinones. 5) The most plausible feature of the biosynthesis of a group of anthraquinones in the two chemical strains of Penicillium islandicum Sopp. is mapped out in Fig. 4 in the text.