Question
I took a picture of a bright green catapillar on Sunday & cannot find a picture online that tells me what it is.  "He" is bright green & as thick as a pinky finger. "He" was crawling down a tree & across the path & I was at a pull-off on the Colonial Parkway in Yorktown,Va. "He" was as long as the Bic lighter my husband put next to it. "He" was smooth with no fuzz to be seen and moved rather fast.

What is he?  I can fwd a picture from my cell phone if you want.
Thanks for the time you have spent on this.

Answer
I did get the pictures thanks! And I think it is a luna moth caterpillar. Either that or one of the Sphinx moths. It was hard to tell some of the ID features from the pictures. Luna moths vary so much from green to brown that it is sometimes hard to ID them. The Sphinx moths have horns on one end but it was hard to see if yours did or not . Therfore I would say it was a luna moth.