Recursively changes rights for directories only?

[Lance Hoffmeyer <lanceh@ibm.net>]

As root I moved a directory structure.  So that any user could read/write files I recursively changed modes for 
all files and directories to rw (i.e. chmod 666 *).  Dumb me, eh?  I now need to recursively change all directories only 
to xr instead of rw.  What is an easy and quick way to do this?  I thought of using 'ls -dR' and piping 'chmod' through it:

ls -dR | chmod 555 * 

but ls -d just gives me . .. and no directory names.

What should I do to change these rights?

Lance