If your in the southeastern united states it is most likely a cotton mouth which is poisonous. they also smell like cucumbers.
cottonmouth
Cottonmouth. Venomous bite.
Cotton mouth
The Cottonmouth - a highly-venomous species.
The Cottonmouth - a highly-venomous species.
A big one. With a big mouth. My wife says maybe bigbird. LOL
The Cottonmouth - a highly venomous species.
Cottonmouth (white mouth). The answer's in the question.
Turtles, Aligators, Snakes, and different types of fish, White owls
The 'Cottonmouth' - a highly venomous snake species !
The white rhinoceros typically lives in grasslands, savannas, and open woodlands. They have a wide mouth adapted for grazing on grasses.
Assuming you're talking about the snake's mouth - the species that immediately comes to mind is the cotton-mouth or water moccasin.