On a mixed culture of Physarum polycephalum and Candida utilis, yeast cells ingested in the living plasmodium are digested, and remnants of the cell wall are found in the plasmodium in addition to cells in an almost intact form with intracellular highly dense substances. When growing yeast cells are treated with an extract from plasmodia the cell wall and intracellular substances are also disintegrated. The digestion, however, did not advance to produce spheroplasts or protoplasts under the condition employed in this experiment.
γ-Hydroxy-γ-methylglutamic acid (γ-HMGA) was found to occur abundantly in nine species out of eighteen fern plants examined, but no correlation was recognized between the existence of this amino acid and the taxonomic position of the ferns. In ferns containing γ-HMGA, its amount exceeded that of other free amino acids at earlier stages of the development, but decreased gradually in the course of growth, while the contents of glutamic acid and/or glutamine increased and became dominant amino acids in place of γ-HMGA. In ferns lacking γ-HMGA, however, glutamic acid and/or glutamine were the major free amino acids hroughout the growth. The presence of a substance that appears to beγ-methyleneglutamic acid was detected inAdiantum pedatum, though in a very small quantity.
vascular system in Paeonia japonica (Makino) Miyabe et Takeda was studied with the special reference to the vascular relationships between foliage leaf traces and reproductive floral parts. In the floral axis, a central vascular ring and five cortical strands were observed. The central vascular ring provides traces for petals, stamens and carpels. The cortical strands provides traces mainly for sepals, petals and some extent of stamens as well. The leaf traces give rise to cortical strands of the floral axis above the node of the uppermost foliage leaf. Both arrangement of foliage leaves and order of sepals are maintained spirally in a 2/5 phyllotaxis, but its spiral order becomes inconspicuous at the inner floral parts of petals and stamens having more tendency to be whorled. In addition, tepals of three types were observed according to their vascularization; the sepaline tepal, petaline tepal and transitional tepal. No centrifugality was observed in development of androecium. The Paeoniaceae should be replaced from Guttiferales to Magnoliales based on the results of floral vascular anatomy.
This report is concerned with quantitative treatments for plastochronic changes of the apex in superficial view as a supplement to the first paper7) of the present series, which dealt with the anatomical analysis of superficial and transectional views of the vegetative shoot apex of Clethra barbinervis Sieb. et Zucc. The bases of young leaf primordia directly surrounding the apex may be expanding considerably at the expense of the area of the shoot apex. Thus, changes in area of the apex occurring during a plastochron may be intimately correlated with the expansion of the bases of young leaf primordia as well as with that of the apex itself. The growth processes, discussed anatomically in the first paper, are checked quantitatively in the present study.
The life history of Desmarestia tabacoides Okamura has been studied in culture. Unilocular sporangia lie embedded in the superficial layer of the cortex. The zoospores develop into minute filamentous thalli (gametophytes) which are monoecious. The formation of both oogonia and antheridia is induced under the culture conditions of comparatively lower temperature and shorter photoperiod. The fertilized eggs germinate inside the oogonia to form monosiphonous filaments which develop into pseudoparenchymatous Desmarestia plants (sporophytes). The sporophytes grow well at 10-18° in a 10-14-hr photoperiod and bear unilocular sporangia at 14-22° in a 10-14-hr photoperiod.