I'm just confused as to why this code isn't working. It says tongueLength doesn't exist...

namespace Treehouse.CodeChallenges
{
    class Frog
    {
        public readonly int TongueLength;
        public readonly int ReactionTime;
        public readonly int FlyReactionTime;
        public readonly int DistanceToFly;

        public Frog(int tongueLength, int reactionTime, int flyReactionTime, int distanceToFly)
        {
            TongueLength = tongueLength;
            ReactionTime = reactionTime;
            FlyReactionTime = flyReactionTime;
            DistanceToFly = distanceToFly;            
        }

        public bool EatFly(int distanceToFly)
        {
            return tongueLength >= distanceToFly;
        }

        public bool EatFly(int distanceToFly, int flyReactionTime)
        {
            return reactionTime <= flyReactionTime;
        }
    }
}