Hi, Haven't been checking the list for a while. what I think you want to do is look at the function plotMAhex in the new hexbin package. if that doesn't work for you you can try: hbp<-plot(hexbin(MA$A[,1],MA$M[,1]),main="MA plot") pushHexport(hbp$plot) grid.points(MA$A[mypoints,1],MA$M[mypoints,1],col=2) Nicholas