Getting Off Book

More on the essence of theater being alive onstage.  As I've mentioned I've been working on a production of Shakespeare's Pericles for the past month and there's one joke that has completely baffled me this whole time.

LYSIMACHUS
Well, call forth, call forth.

BOULT
For flesh and blood, sir, white and red, you shall
see a rose; and she were a rose indeed, if she had but--

LYSIMACHUS
What, prithee?

BOULT
O, sir, I can be modest.

So, on paper this joke didn't make any damn sense this whole month.  IF SHE HAD BUT WHAT??  But today I read the joke aloud for the first time, the joke isn't really in what he doesn't say, it's in what he does say "a rose" "arose" -- aroused.  If only you could get her aroused.  Because Marina is beautiful but sworn to chastity.  Perhaps this is the most trivial example of the importance of living theater, but seriously it's going to improve the hell out of the scene for this to be an intelligible joke.  If any one else has any other ideas about this joke feel free to email or post them, it's from Act IV, Scene 6.  Maybe I'm still overlooking something.