抄録
A presentation of an aberrant 4:4 ascus was made in colour photomicrograph. Means for the recognition of aberrant 4:4 asci and the possible origin of conversion ascus types were explained. A new method was introduced to extract the fundamental ascus types of the two pairs of chromatid complements from the ascus types of 4-chromatid conversion. A discussion was done on the role of aberrant 4:4 type in choosing one kind of theories from the two which were different in the manner of hybrid DNA formation.
