Exiting witha GUI Button

okay hello, i was just wondering i have found a code and it works good but it doesnt exit the map when i click the GUI button, is there anyway i could do this so that when i click the GUI button again the “Map” would disappear ??

var myBox : Transform;

function Start()
{
myBox.renderer.enabled = false; // hide it
}

function OnGUI()
{
if (GUI.Button (Rect (10, 10, 100, 20), “Map”))
myBox.renderer.enabled = true;

}

var myBox : Transform;
var showMap = false;

function Start()
{
 myBox.renderer.enabled = false; // hide it
}

function OnGUI()
{
 showMap =  (GUI.Toggle (Rect (10, 10, 100, 20), showMap, "Map");
 myBox.renderer.enabled = showMap;
}