Mice and Rats

How can you tell the differance between a mouse and a rat? I have been feeding my baby ball fuzzy mice and he loves them (great eater). I bought a few differant sizes last week from a Pet Shop that sells them one at a time, and i have a feeling that the hopper mice they gave me are actually rats. There faces are much longer than the fuzzy mice and they kind of look differant. But i am no rodent expert.

take a look at the mice , rats, and asf forums on here

i checked it out, but they both look pretty similar. the reason i asked to begin with is because he came out of his hide very quick as he usually does when he smells food, but as soon as he got close enough to examine the mouse/rat he backed off and wanted nothing to do with it. but i know my snakes behavior and he is definatley hungry. just curious. i will do some more research
:D

Post pictures.

Rats and mice have different faces, but when they're dead/frozen/thawed, it's a bit harder, since they can be a bit squished or the fur can be fluffed to distort the lines.

As far as I know sizes on mice though, a hopper mouse 'sized' rat would be almost hairless though.