It was glued to the leaf, and hanging down from it. When I went to knock it off with the stick, it just fell apart, kind of like paper does that has burned black. Except it had this black liquid, inside it.
I looked for more like that, thinking I could get a pic of it, and disect it to see what was going on here.
I was watering, just before I had to cook supper, so no time to search really close. I will seek out more of these strange black hornworms.
Funny mine are tomato hornworms on the tobacco, they have the tomato markings. And you have the tobacco hornworms on tomatoes...