Trouble hitTesting an array.

[Vadersapien]

Hey everyone,
I am having trouble hitTesting items in an array...here is my full code:

stop();

var gameStarted:Boolean = false;
var gamePaused:Boolean = false;
var generateSpeed:Number = 7;
var speed:Number = 0;
var score:Number = 0;
var health:Number = 100;
var spiderArray:Array = [];

hud.pauseBar._visible = false;

menuSound.stop();
inGameSound.start();

this.createEmptyMovieClip('spiders',this.getNextHighestDepth());

this.onEnterFrame = function() {
    if (!gamePaused && gameStarted) {
        score++;
    }

    if (score == 1000 || score == 2000 || score == 3000 || score == 4000 || score == 5000) {
        generateSpeed += 3.5;
    }

    if (score == 6000) {
        generateSpeed = 28;
    }

    if (generateSpeed>28) {
        generateSpeed = 28;
    }

    if (health<0) {
        health = 0;
    }

    if (health == 0) {
        delete this.onEnterFrame;
        gameStarted = false;
        inGameSound.stop();
        gameOverSound.start();
    }
};

hud.onEnterFrame = function() {
    if (gameStarted && !gamePaused) {
        this.swapDepths(this.getNextHighestDepth());
    }
};

car.onEnterFrame = function() {
    if (gameStarted && !gamePaused) {
        if (Key.isDown(Key.UP)) {
            this._y -= speed/2;
        }

        if (Key.isDown(Key.DOWN)) {
            this._y += speed;
        }

        if (Key.isDown(Key.LEFT)) {
            this._x -= speed;
        }

        if (Key.isDown(Key.RIGHT)) {
            this._x += speed;
        }
        speed += 0.3;

        if (speed>=15) {
            speed = 15;
        }

        if (this._x<=37.35) {
            this._x = 37.35;
        }

        if (this._x>=762.65) {
            this._x = 762.65;
        }

        if (this._y<=42.65) {
            this._y = 42.65;
        }

        if (this._y>=507.40) {
            this._y = 507.40;
        }
        
        for(x in spiderArray){
            if (this.hitTest(_root[spiderArray[x]])) {
                _root[spiderArray[x]].removeMovieClip();
                this.removeMovieClip();
                spiderArray.splice(x, 1);
            }
        }
    }
};

grass.onEnterFrame = function() {
    if (gameStarted && !gamePaused) {
        this._y += speed;
    }

    if (this._y>0) {
        this._y = -200;
    }
};

spiderGenerator.onEnterFrame = function() {
    if (!gamePaused && gameStarted) {
        this._y -= generateSpeed;
    }

    if (this._y<0) {
        growSpider();
        this._y = 600;
    }
};

function growSpider() {
    if (!gamePaused && gameStarted) {
        spiderCount = 0;
        while (spiderCount<Math.floor(Math.random()*(9-7))+7) {
            spiderCount++;
            randomX = Math.floor(Math.random()*(745-55))+55;
            spider = spiders.attachMovie('Spider', 'Spider'+spiders.getNextHighestDepth(), spiders.getNextHighestDepth(), {_x:randomX, _y:-32});
            spiderArray.push(spider._name);

            spider.onEnterFrame = function() {
                if (!gamePaused) {
                    this._y += speed/2;
                    this.play();
                }

                if (this._y>=632) {
                    this.removeMovieClip();
                }
            };
        }
    }
}

function transitionToNextFrame() {
    nextFrame();
} 

Any ideas why it's not working?