CORRELATED VARIATION OF CHIASMA FREQUENCY AND SYNAPTONEMAL COMPLEX LENGTH IN LOCUSTA-MIGRATORIA

Mean diplotene chiasma frequency is shown to be significantly and posi tively correlated with mean synaptonemal complex (SC) length in 21 mal es of Locusta migratoria belonging to three different families. This m ay reflect a direct causal connection between SC length and chiasma fr equency or an indirect relationship arising from the action of other f actors with effects on both parameters. Various interpretations of the correlation are discussed in the light of old and new information on synaptic and recombinational processes during meiotic prophase I.