Thanks everyone,
Grouperhead, I'm not really too sure if it is a Butler's, I searched on the net for Michigan snakes and that was the one it looked like. Tom put a call into a professor at the local college, if it is a butlers, the web site said they are uncommon. I would have loved to have found it when (if its a female) it was pregnant, from what I read, they have live births. So cool, I do have another photo of its total body, if interested I will post it. We have it in a 10 gallon tank with a screen lid on it, with grass and leaves right now.
Iam totally amazed how little its head is after seeing it with the frog in its mouth, it can't be much bigger then a dime.
Lisa