蘚類の〓歯の発生学的研究 I

タマゴケの朔歯の発生について

抄録

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.