Hey...Like everyone has said it is a tomato worm. I wouldn't use sevin dust because it harms the good bugs too. Just pick them off and give them to your chickens. If you should find one with what looks like eggs on its back, let it be. The eggs are from a wasp that feeds on these worms. Next year you wont have a problem with them because the wasps will hang around......Also the horn on its back end will not hurt you. It is just meant to scare you.
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