Greys

gistfile1.txt

library(ggplot2)

x <- data.frame(y = rnorm(100), g = rep(letters[1:4], 25))


ggplot(x, aes(y = y, x = g, fill = g)) + 
  geom_boxplot() + 
  ylim(c(-15, 15)) +
  scale_fill_manual(values = grey(c(0, 0.5, 0.9, 1))) +
  theme_bw()