1. Genic analysis concerning the shapes of spikes in the hexaploid plantains revealed that the branched spike (b) is a simple mendelian recessive to the single form. Spikes of polystachya are not always branched, but some show single spikes, probably owing to the humidity of specially high grade. 2. In the common tetraploid plantain, pale yellow seedling-cotyledons were found by the writer to be inherited by the recessive duplicate genes (y1, y2) to the normal green. 3. A strain heterozygous for variegata in the common tetraploid plantain was found, which segregated normal and variegata in an abnormal ratio of about 1:2, contrary to expectation of an ordinary segregation ratios of 15:1 or 3:1. The writer wishes to express his cordial thanks to Prof. Shinotô of International Christian University, who gave valuable advices in the course of the present work.
1. Viable pollen grains exude a liquid as soon as they adhere to the stigma, manifesting at the same time a form change by the formation of wart-like bulgings covering the surface. This apparent form change proceeds after a definite pattern, and the grains return to their original smooth shape in about thirty to sixty seconds from the beginning of the process. The phenomenon was recognized hitherto in 28 species belonging to 19 genera of Gramineae. 2. The liquid accumulates at the point of contact of the grain with a stigma hair, and fills out the space between them. The liquid can be always observed when germination occurs, whereas pollen grains which do not exude it are incapable of germination.
1. With a variety of horse beans, the variation in the water content, the specific gravity of the tissue powder and the amount of reducing sugars caused by the low temperature treatment at 7°C and 0°C were studied. 2. The water content of the material treated at 7°C was much greater than that treated at 0°C. 3. On the contrary, the specific gravity of the tissue powder was smaller in the former case in the latter. 4. The amount of reducing sugars both in the material treated at 7°C and at 0°C showed the similar change and it increased with the progress of the treatment up to 14 days. 5. It was found that the treatment at 7°C was more effective than that at 0°C as regards to the vernalizing effect in the field experiment. 6. The effect of vernalization increased with the progress of the low temperature treatment and the period of 21 days was the most effective for vernalization in the present experiments. 7. The fall of flower buds prior to the sufficient flowering was sometimes observed on the plants grown from the seedlings which were treated at low temperature during insufficient time length.
Mi havis kelke da observadoj por klarigi funkcion de vegeta nukleo en la dauro de la kreskado de polentubo sur la kulturaj medioj, precipe pri la agado de la nukleo. Giaj rezultoj estas subaj:- 1. En polenoj de Oenothera au Impatiens, ne ciuj polentuboj enhavas nukleojn: t.e. iu polentubo en kiu enhavas neniom da nukleo. 2. Polenoj de Oenothera povas plene kreskigi polentubon, antau ol la vagetaj nukleoj ankorau disiras, se ec je unu nukleo. 3. La distancoj inter vegeta nukleo kaj genera nukleo kaj la ekstrema fino de la tubo estas ne konstanta. Ekzempre: genera nukleo alproksimigas provizore al vegeta nukleo antau ol gia dividigo. 4. Polenoj transmetitaj de 25% sukera solvajo al 5% solvajo ne germas polenan tubon, tamen, interne de la poleno gia nukleo faras konduton same kiel en la polena tubo. 5. Lau nia ordinara kono, oni komprenas ke vegeta nukleo havas iun funkcion por kreskado de la polentubo, sed mi tamen pensas ke gi havus rilaton al la dividado de la genera nukleo.
1. The initial quadrant, showing 4-celled stage in cross section, is divided by the first periclinal walls into the amphithecium and the endothecium. The original amphithecium is divided by the second periclinal walls into inner and outer layers. 2. The inner peristomial layer arises from the inner amphithecial layer, and comes to be composed of 32-48 longitudinal rows of cells by the formation of anticlinal walls. 3. By the formation of periclinal walls the amphithecium is divided into outer and inner cell layers, of which the inner layer comes to have sixteen cells in cross section by forming anticlinal walls. These sixteen cells undergo no further division. 4. The ridges of thickening, representing the teeth, are laid upon each of the outer periclinal walls of inner and outer peristomial cells, respectively. 5. Before the deposition of the peristomial thickenings, the nucleus in the cells relating the formation of teeth is enlarged. And then the protoplasm of both the inner and outer peristomial cells moves towards their outer sides respectively, while these of circumscribed cells towards their inner sides. Accompanying with the thickening the cytoplasm and nuclei gradually shrivel away and disappear. 6. The thickening of the inner teeth begins at the same time with that of the outer teeth. However, the thickening in the uper portions of the outer teeth happens latter than that in their basal portions. 7. After the formation, the processes of the inner peristome longitudinally splits along the keel line.