On the Nuclear and Cell division of a Plankton diatom Coscinodiscus subbuliens, Jörgensen
1923 年 37 巻 439-444 号 p. en96-en108_2
詳細
1923 年 37 巻 439-444 号 p. en96-en108_2
1. The nuclear division of diatoms occurs not only in the night, as it is generally assumed, but also in the day time, if they are subjected to a certain condition.
2. The movementof the nucleus toward the girdle region is one of ther emarkable phenomena in the mitosis.
3. The origin of the central spindle is not studied. It has been left for the further investigations.
4. Well-developing chromosomes are slender in form as those of Surirella calcarata studied by LAUTERBORN. The number of chromosomes have not been precisely counted; it lies perhaps between 12 and 20.
5. The true centrosome appears neither in the vegetative condition nor in the mitosis but centrosome-like bodies have been found in the certain figures of the mitosis as a temporary occurrence.
6. The cell division commences with the formation of a cell plate which is divided into two plates first in its central part, appearing as a fusiform fissure. The division in the marginal region of the cell plate follows it giving rise to an appearance of a constriction of the cell.
