On red bay (I think), Persea borbonia. Spicebush swallowtail, which is very similar, also uses bay trees, but the difference is in the first abdominal segment - the blue spot is adjacent to the leading edge of the orange spot, not within it. Apparently the tail end of the young Palamedes larva is white, rather than the dark patch of Spicebush, if you see one of the bird-poop-like early instars.
While researching this one I found that several Papilio, including this one, have been moved to genus Pterourus - not such a pretty name!(1)