It's an amazing looking creature. Click on the photo to enlarge it. It has a fake eye below each white stripe. It also has a face on its rear end (the end with the red horn).
The tobacco hornworm is the larval stage of the beautiful Sphinx moth. I'm very fond of the moths, which become active as the sun goes down. I have many 4-o'clocks and a few daturas in my garden, so the Sphinx moth is a common visitor. Today when I went into my garden for the first time since last Monday, I found one of my fall tomato plants defoliated, with two large hornworms who look as though they're getting pretty close to the point where they will drop off the plant and burrow into the soil to pupate over winter. The other tomato plants are fine. I took one of the worms off the plant and gave it to the chickens to eat, but I left one there. What the heck. The plant is already ruined -- there's no way it can recover and produce tomatoes before the first frost -- and I'll be glad to have the moths in the garden.