I found a lot of these Battus Philenor caterpillars feeding on a large planting of Dutchman's Pipevine at the butterfly garden of a local nursery called The Natural Gardener. These four images are of two specimens which I think were in the final instar. Then I found a large group of very early instars feeding together here: , and finally I found yet another group which were all in the same middle instar: .