graph of overlapping normal distributions

[Michael Bailey <jm-bailey@northwestern.edu>]

In order to demonstrate the concept of effect size to my class, I  
want to show them two figures, each of overlapping normal  
distributions. (Same mean differences, different variances, to show  
why variance is part of effect size). jmp makes it very easy to  
generate random normal data, although I haven't figured out yet how  
to change the SD. More importantly, I can't figure out how to graph  
two distributions on the same axes.
Thanks for any help.
Mike Bailey