羊齒植物の細胞學的研究

1. In the present paper the bodies in the cytoplasm which stain vitally with aqueous solution of Janus green (cf. Sorokin 1938) are designated as chondriosomes in the cells of Polypodiaceous plants.<br>2. The plastids and chondriosomes are distinct from each other and exist side by side in all the stages of the life cycle. The latter stains vitally with aqueous solution of Janus green, while the former does not.<br>3. The plastids and chondriosomes increase in number by their own division.<br>4. In general, the plastids are larger than the chondriosomes, but in some cases the former become smaller resembling the chondriosomes. Even the latter cases these two types of bodies can be distinguished from each other when aqueous solution of Janus green is used.<br>5. In the spore several plastids (leucoplasts) and many chondriosomes which are small granulous, rodlet-like or rosary-like are observed.<br>6. Before germination of the spore the leucoplasts change into chloroplasts. In the prothallium cell there are many large chloroplasts and small chondriosomes.<br>7. In the spermatogenous cell there are observed from several to ten small leucoplasts and many chondriosomes.<br>8. In the spermatid from several to ten small leucoplasts and many chondriosomes are contained. As the spermatozoid approaches to its completion the leucoplasts become larger, accumulating starch grains within them.<br>9. The plastids and chondriosomes of the spermatozoid are cast away during the active swimming of the spermatozoid.<br>10. In the young egg cell large spherical leucoplasts (several to ten) and many small granulous, rodlet-like or rosary-like chondriosomes are seen. In the completed egg cell all the chondriosomes are granulous.<br>11. The plastids and chondriosomes of the new plant derive from these of the egg cell only.<br>12. In the cells of sporophyte many large chloroplasts and small granulous, rodlet-like or rosary-like chondriosomes are contained. In the case of subterranean stems, roots and rhizoids the leucoplasts and chondriosomes are seen in the cell.<br>13. During the course of sporogenesis the spore mother cell contains small leucoplasts and chondriosomes which are gathered on the separation plane of anaphase in meiosis and distributed into the spore cells.<br>14. In the spore cells several leucoplasts and many chondriosomes are contained. As the spore cell approaches its completion the leucoplasts gradually increase in their size.