The first 2 attachments are of a very large Caterpillar that sent my Mom running for the hills, claiming she would “…never go outside ever again.” (she has since gone outside…) After finding your site I think it is a Luna moth Caterpillar, but I can’t find a picture that has the same patterns. Do they vary that much? or is this some other creature? The second attachment shows a very interesting “X” on his rear end. The 3rd attachment came from my tomato garden and I think it is a tomato horn worm with parasitic wasp larvae. This creature and attachments just about sent my Mom into convulsions. (It creeped me out too.) By the way, we live in Elkridge, Maryland. Also just wanted to say that your site is terrific it has helped me several times this summer identify weird and wonderful things in our yard.
Your caterpillar is another Giant Silkworm, the Polyphemus MOth.