Snakes smell with their tongues. When a snake sticks out its tongue it smells its surroundings. The tongue collects scents from whatever it touches and from the air around it. When the tongue goes back into the mouth the forked tongue touches a l sensory spot called the Jacobson's organ on the roof of the mouth and tells the snake what it smells. Snakes also have a small notch in their lips that they can stick their tongues through so they don't need to open their mouths.