[plt-scheme] PLoT and legends

Looking over the documentation at
     http://docs.plt-scheme.org/plot/
I see ways to mix several datasets on the same plot, which is wonderful, but no 
textual way to tell which is which.  Is it possible to create a plot legend or 
key that associates the color/shape of each plot in a mix with a label?

Another mystery is that mix* is mentioned in the second paragraph of section 
1.2 but is never described anywhere (or mentioned again).  What does it do? 
Does it still exist?
> (require plot)
> mix
#<procedure:mix>
> mix*
. . reference to an identifier before its definition: mix*

It would be cool if there were a mix* that let me label things.

Thanks,
Grem

-- 
------ __@   Gregory A. Marton                 http://csail.mit.edu/~gremio
--- _`\<,_                                                     617-775-3005
-- (*)/ (*)           Hiroshima '45, Tschernobyl '86, Windows '95.
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