not an inch worm. What is it?
Who will this become?
gessieviolet, When you say "not an inch worm" did you mean not a Geometridae? Or were you refering to a species you know as inch worm? I think it might be a Geometridae, a member of the family that includes loopers, inchworms and spanworms. But I can't tell how many sets of prolegs it has. At any rate, I can't find a similar looking cat in my field guide.
You can re-post on the insect and spider ID forum if no one has a possitive ID here.