My son found a caterpillar on our porch yesterday. He's 4, so i thought we'd use it as a learning opportunity. I put it in a large jar with some misted leaves from our yard...didnt know which kind of leaf, since we didnt *find* the caterpillar on a leaf, we found it on our patio...but we put a few different kinds in there... And i can't for the life of me find out what kind of caterpillar it is. It was fairly thin (not big huge fat things like some), it was mostly a mustardy yellow color with pairs of black spots running down the length of the body with smaller white spots on top of the black spots...It had long hairs but they were sparse...I wouldn't call it a "fuzzy" caterpillar at all. no other unique features like eye spots or tails or anything. I was going to take a photo of it this morning, but i can't get to him because he has encased himself in what look like spider silks, inside a leaf, folded over. It's white and fuzzy, almost like mold, only it is very sticky and before i realized what it was i tried to gently pull the leaf apart but it wouldn't budge. the stuff is strong, which is when i figured it had encased itself in the leaf. But, it doesnt seem to be making a chrysalis because i can still see the caterpillar in there...and he's moving, very slightly in there.
this is a great site for caterpillar id.
We have caterpillars that have a similar beginning to their chrysalis. After the spider web looking silks it then forms a chrysalis.
This is a good site for identifying moth caterpillars: http://www.pbase.com/tmurray74/moth_caterpillars
Moths are much more numerous than butterflies and most caterpillars you find will be moth caterpillars. It sounds like your caterpillar is pupating. If you find a caterpillar walking around on the ground, not on a plant, that's often a sign that it's looking for a place to pupate. A butterfly pupa is called a chrysalis. It hangs from a short stalk. A moth pupa is similar, but doesn't hang from a stalk. Some moths form a cocoon around the pupa. The cocoon may be made of silk (often mixed with the caterpillar's hairs) or it may be made by folding over a leaf and fastening it with silk.