Cool. Good for both kids and Lepidopterans alike:) My immediate goal is to inspire non BF gardeners and even non gardeners to start planting for butterflies, starting c the Monarch. I got most of my neighbors in on the act, and upkeep is minimal, since most plants I use are native. I even have a neighbor who is an "accidental" BF gardener, as he has Milkweed and Queen Anne's Lace growing in profusion. He was going to pull it all, but I talked him out of it. Now he helps bolster the Monarch and Swallowtail population on our cul de sac.

I don't know. Maybe Red-spotted purple butterfly egg. Maybe oak "worm" egg.

You are confused for some reason, are confusing the issue. Clearly, the OP had identified the Tobacco hornworm, Manduca sexta. Do you not believe that someone new to the gardenweb or new to gardening can utilize the internet in a useful manner? I know...it seems to be rare, but I am proud of David. Sphingidae is a large family of moths. They are ALL correctly called Sphinx moths. Our OP plucked the caterpillars from his tomato plants and went to work finding a proper ID. The caterpillars of most (not all) Sphinx moths are hornworms and as a family, can be found on many kinds of plants. They tend to be host specific. Now, Kimmsr.....there are hornworms that feed on Solanaceous plants. I have never seen Tobacco hornworm on anything but a tomato or datura or pepper. I have also never seen nor heard of nor read of any other kind of hornworm (Sphingidae) on those plants. I hope that you have a better understanding, now. It can be confusing, for sure. But understanding the host /pest relationship with this particular moth family is extremely important. One can pretty much ID a hornworn if the host plant is identified....no picture of the caterpillar required. In this instance, we had an OP who was one step ahead of the usual 'newbie '. David used the internet. All he wanted to know is if he planted some tobacco plants would the Manduca sexta lay eggs on those and stay away from his tomatoes.

University-based research has shown that such devices attract and kill more beneficial insects than insect pests.