In view of the small size of the chromosomes or owing to unfavorable disposition,
sometimes some confusion regarding the determination of the exact nature of aberration, e.g., erosion or constriction, made placement of aberrations to a particular type difficult, for which reason the more important and clear aberrations were put under ‘‘major’’ types and the relatively less significant ones including the gaps and the other ‘‘difficult-to-place’’ ones were pulled together under the ‘‘other’’ types. The total aberration frequencies, i.e., the sum total of ‘‘major’’ and ‘‘other’’ type aberrations, obtained from six specimens of each series were taken into account in the
statistical analysis.