Amitosis in Three Species of Euglena

抄録

Amitosis is recorded for Euglena acus, Euglena spirogyra and Euglena viridis, occurring only in biphasic culture. The process is a nuclear fragmentation not connected with reproduction, the product being a binucleate cell.
The binucleate cell is capable of subsequent mitosis in Euglena acus and Euglena spirogyra, the half-nuclei dividing simultaneously.
Cell cleavage following this mitosis produces two binucleate cells. Rare miscleavage results in cells with one half-nucleus (approximately half the specific chromosome complement) and with three half-nuclei (one-and-a-half times the specific chromosome complement). These types of cells are viable and their progeny retain the cytological characteristics of the species.