抄録
1. The cytological behaviour of an unmodified diploid isolated after exposure of the control yeast, BY 1, to camphor for 90 days is described.
2. The recovered diploid is indistinguishable in its cytological behaviour from the parent yeast. As in the control, there is no synchronization in (a) the reproduction of the chromosomes, (b) the separation of the chromatids and (c) the onset of the telophasic changes, Karyokinesis and cytokinesis also do not parallel each other.
3. Rare precocious anaphases are illustrated. It is indicated how a gene mutation stabilizing the doubled chromosome complement is all that would be necessary to convert cells showing precocious anaphases into regular autotetraploids
