Chromosomal inversion In(3R)C and extra dorsocentral and scutellar macrochaetae are correlated in Asturian natural populations of Drosophila melanogaster in that selection for extra bristles produced an increase in In(3R)C frequency. In the present work two populations with significantly different frequencies of the In(3R)C inversion were created and a significant positive correlation between In( 3R)C frequency and frequency of individuals carrying extra bristles was found. This result confirms the correlation between bristles and In(3R)C. In addition, the correlation between the two characters is also demonstrated at the individual level.