diff --git a/lib/OpenLayers/Map.js b/lib/OpenLayers/Map.js
index 8384befc81..566e75c4d1 100644
--- a/lib/OpenLayers/Map.js
+++ b/lib/OpenLayers/Map.js
@@ -954,7 +954,7 @@ OpenLayers.Map = OpenLayers.Class({
      *
      * Paremeters:
      * layer - {<OpenLayers.Layer>} 
-     * idx - {int} 
+     * delta - {int} 
      */
     raiseLayer: function (layer, delta) {
         var idx = this.getLayerIndex(layer) + delta;