Static variables problem

i have a health bar script, and i made a static variable in it. i made it so a monster follows the main character. The monster's code also has a static variable. In the main character's code, i want to make it so when the monster hits it, it does the health bar's static variable minus the monster's static variable. the health bar's script is called bar, and the monster's script is called beholder. here's the code for the character:

var speed : float = 6.0;
var jumpSpeed : float = 8.0;
var turnSpeed : float = 3.0;
var gravity : float = 20.0;

bar.barDisplay = 100; 
beholder.damage = 5;

private var moveDirection = Vector3.zero;
private var turnDirection : float = 0;
private var grounded : boolean = false;

function OnTriggerEnter(hit : Collider)
{
    if(hit.gameObject.tag == "Beholder")
    {
        Debug.Log("hit for " + beholder.damage + "points");
        bar.barDisplay -= beholder.damage;
    }
}
function FixedUpdate() {
    if (grounded) {
        // We are grounded, so recalculate movedirection directly from axes
        moveDirection = new Vector3(0, 0, Input.GetAxis("Vertical"));
        moveDirection = transform.TransformDirection(moveDirection);
        moveDirection *= speed;

        turnDirection = Input.GetAxis("Horizontal");
        transform.Rotate(0, turnDirection * turnSpeed ,0);

        if (Input.GetButton ("Jump")) {
            moveDirection.y = jumpSpeed;
        }
    }

    // Apply gravity
    moveDirection.y -= gravity * Time.deltaTime;

    // Move the controller
    var controller : CharacterController = GetComponent(CharacterController);
    var flags = controller.Move(moveDirection * Time.deltaTime);
    grounded = (flags & CollisionFlags.CollidedBelow) != 0;
}

@script RequireComponent(CharacterController)

everything else works, but unity says that the identifiers beholder and bar are unknown...

"beholder" and "bar" are not the names of your classes. (That is, they are not the names of the scripts.) The naming convention in Unity is to use uppercase for the first letter of a class's name. So here is what you would use in the script you posted:

Bar.barDisplay = 100; 
Beholder.damage = 5;

And in those scripts, named Bar, and Beholder, respectively, you need these declarations:

static var barDisplay;
static var damage;