I then checked on the carrots and saw another caterpillar hanging out on the greens, this one I recognized and left alone. That's right I murdered the one that was unfamiliar to me, and left the one I knew alone. Is there a word for gardening xenophobia? my googling does not lead me to an answer..
Once back inside with my bowl full of tomatoes (they will become pickles soon enough) I looked for images of the deceased. I found this
I did find out is that this caterpillar (who was bigger and had more white things on it) is really a tomato hornworm. The white things (which I thought may have been maggots or something equally gross) are actually the cocoons of some kind of wasp- which apparently eats its way through the hornworm to form the cocoon on the outside. So by throwing the whole things into the BBQ I really performed a mercy killing. The poor thing was being eaten from the inside! The wasps would have hatched and sought out other hornworms to feast on! (which would have been good for garden, except for the fact that there would be wasps in it)
The caterpillar that I did recognize was this one