[R] Legend and Main Title positioning

[Antje]

Hi folks,

can anybody give me a hint how to solve the following problem?
I have several plots in one window like this:

layout(matrix(c(1,2,3,4), nrow = 2, byrow = TRUE))
plot(rnorm(100))
plot(rnorm(200))
plot(rnorm(300))
plot(rnorm(400))

Now, I'd like to create a legend below each plot and generate a common title.
How can I do that?


Antje