diff --git a/lib/straps.js b/lib/straps.js
index ec487570..3e638b0b 100755
--- a/lib/straps.js
+++ b/lib/straps.js
@@ -252,16 +252,19 @@ var Base = this.Base = new function() { // Straps scope
 		},
 
 		extend: function(src/* , ... */) {
-			var ctor = function() {
-				// Call the constructor function, if defined
-				if (this.initialize)
-					return this.initialize.apply(this, arguments);
+			var ctor,
+				base = this;
+			// Look for an initialize function in all injection scopes and use
+			// it as the actual constructor.
+			for (var i = 0, l = arguments.length; i < l; i++)
+				if (ctor = arguments[i].initialize)
+					break;
+			// If no initialize function is provided, create one that simply
+			// calls the base constructor.
+			ctor = ctor || function() {
+				base.apply(this, arguments);
 			};
 			ctor.prototype = create(this.prototype);
-			// Add a toString function that delegates to initialize if possible
-			ctor.toString = function() {
-				return (this.prototype.initialize || function() {}).toString();
-			};
 			// The new prototype extends the constructor on which extend is
 			// called. Fix constructor.
 			define(ctor.prototype, 'constructor',
diff --git a/src/item/Group.js b/src/item/Group.js
index 6e42c04f..f7558d09 100644
--- a/src/item/Group.js
+++ b/src/item/Group.js
@@ -89,7 +89,7 @@ var Group = this.Group = Item.extend(/** @lends Group# */{
 	 * });
 	 */
 	initialize: function(arg) {
-		this.base();
+		Item.call(this);
 		// Allow Group to have children and named children
 		this._children = [];
 		this._namedChildren = {};
diff --git a/src/item/Layer.js b/src/item/Layer.js
index ff2afaf0..8d60f91a 100644
--- a/src/item/Layer.js
+++ b/src/item/Layer.js
@@ -61,7 +61,7 @@ var Layer = this.Layer = Group.extend(/** @lends Layer# */{
 		this._project = paper.project;
 		// Push it onto project.layers and set index:
 		this._index = this._project.layers.push(this) - 1;
-		this.base.apply(this, arguments);
+		Group.apply(this, arguments);
 		this.activate();
 	},
 
diff --git a/src/item/PlacedSymbol.js b/src/item/PlacedSymbol.js
index 06298ac2..a7766752 100644
--- a/src/item/PlacedSymbol.js
+++ b/src/item/PlacedSymbol.js
@@ -72,7 +72,7 @@ var PlacedSymbol = this.PlacedSymbol = Item.extend(/** @lends PlacedSymbol# */{
 		// Support two forms of item initialization: Passing one object literal
 		// describing all the different properties to be set, or a symbol (arg0)
 		// and a point where it should be placed (arg1).
-		this.base(arg1 !== undefined && Point.read(arguments, 1));
+		Item.call(this, arg1 !== undefined && Point.read(arguments, 1));
 		// If we can handle setting properties through object literal, we're all
 		// set. Otherwise we need to set symbol.
 		if (arg0 && !this._set(arg0))
diff --git a/src/item/Raster.js b/src/item/Raster.js
index 5899222f..3ce86c6f 100644
--- a/src/item/Raster.js
+++ b/src/item/Raster.js
@@ -76,7 +76,7 @@ var Raster = this.Raster = Item.extend(/** @lends Raster# */{
 		// Support two forms of item initialization: Passing one object literal
 		// describing all the different properties to be set, or an image
 		// (object) and a point where it should be placed (point).
-		this.base(position !== undefined && Point.read(arguments, 1));
+		Item.call(this, position !== undefined && Point.read(arguments, 1));
 		// If we can handle setting properties through object literal, we're all
 		// set. Otherwise we need to check the type of object:
 		if (object && !this._set(object)) {
diff --git a/src/item/Shape.js b/src/item/Shape.js
index 3a11335f..4320a82d 100644
--- a/src/item/Shape.js
+++ b/src/item/Shape.js
@@ -22,7 +22,7 @@ var Shape = this.Shape = Item.extend(/** @lends Shape# */{
 	_applyMatrix: false,
 
 	initialize: function(type, point, size) {
-		this.base(point);
+		Item.call(this, point);
 		this._type = type;
 		this._size = size;
 	},
diff --git a/src/path/CompoundPath.js b/src/path/CompoundPath.js
index 9cf5a976..a35313a2 100644
--- a/src/path/CompoundPath.js
+++ b/src/path/CompoundPath.js
@@ -50,7 +50,7 @@ var CompoundPath = this.CompoundPath = PathItem.extend(/** @lends CompoundPath#
 	 * compoundPath.children[1].position.x += 5;
 	 */
 	initialize: function(arg) {
-		this.base();
+		PathItem.call(this);
 		// CompoundPath has children and supports named children.
 		this._children = [];
 		this._namedChildren = {};
diff --git a/src/path/Path.js b/src/path/Path.js
index e844e3a6..4850eb24 100644
--- a/src/path/Path.js
+++ b/src/path/Path.js
@@ -70,7 +70,7 @@ var Path = this.Path = PathItem.extend(/** @lends Path# */{
 	initialize: function(arg) {
 		this._closed = false;
 		this._segments = [];
-		this.base();
+		Item.call(this);
 		// arg can either be an object literal describing properties to be set
 		// on the path, a list of segments to be set, or the first of multiple
 		// arguments describing separate segments.
diff --git a/src/project/Project.js b/src/project/Project.js
index 5f71d2fa..bd1c1e5b 100644
--- a/src/project/Project.js
+++ b/src/project/Project.js
@@ -47,7 +47,7 @@ var Project = this.Project = PaperScopeItem.extend(/** @lends Project# */{
 	initialize: function(view) {
 		// Activate straight away by passing true to base(), so paper.project is
 		// set, as required by Layer and DoumentView constructors.
-		this.base(true);
+		PaperScopeItem.call(this, true);
 		this.layers = [];
 		this.symbols = [];
 		this._currentStyle = new Style();
diff --git a/src/text/TextItem.js b/src/text/TextItem.js
index 91986253..81f132e3 100644
--- a/src/text/TextItem.js
+++ b/src/text/TextItem.js
@@ -38,7 +38,7 @@ var TextItem = this.TextItem = Item.extend(/** @lends TextItem# */{
 		// might be a properties object literal for #setPropeties() at the end.
 		var hasProperties = arg && Base.isPlainObject(arg)
 				&& arg.x === undefined && arg.y === undefined;
-		this.base(hasProperties ? null : Point.read(arguments));
+		Item.call(this, hasProperties ? null : Point.read(arguments));
 		this._content = '';
 		this._lines = [];
 		if (hasProperties)
diff --git a/src/tool/Tool.js b/src/tool/Tool.js
index fbdc2dfb..8f227150 100644
--- a/src/tool/Tool.js
+++ b/src/tool/Tool.js
@@ -51,7 +51,7 @@ var Tool = this.Tool = PaperScopeItem.extend(/** @lends Tool# */{
 
 	// DOCS: rewrite Tool constructor explanation
 	initialize: function(props) {
-		this.base();
+		PaperScopeItem.call(this);
 		this._firstMove = true;
 		this._count = 0;
 		this._downCount = 0;
diff --git a/src/ui/CanvasView.js b/src/ui/CanvasView.js
index 077f2b1e..c523dfe5 100644
--- a/src/ui/CanvasView.js
+++ b/src/ui/CanvasView.js
@@ -34,7 +34,7 @@ var CanvasView = View.extend(/** @lends CanvasView# */{
 		this._context = canvas.getContext('2d');
 		// Have Item count installed mouse events.
 		this._eventCounters = {};
-		this.base(canvas);
+		View.call(this, canvas);
 	},
 
 	/**
diff --git a/src/ui/KeyEvent.js b/src/ui/KeyEvent.js
index c1dcecec..9b80e540 100644
--- a/src/ui/KeyEvent.js
+++ b/src/ui/KeyEvent.js
@@ -22,7 +22,7 @@
  */
 var KeyEvent = this.KeyEvent = Event.extend(/** @lends KeyEvent# */{
 	initialize: function(down, key, character, event) {
-		this.base(event);
+		Event.call(this, event);
 		this.type = down ? 'keydown' : 'keyup';
 		this.key = key;
 		this.character = character;
diff --git a/src/ui/MouseEvent.js b/src/ui/MouseEvent.js
index a520e51b..7727ee3f 100644
--- a/src/ui/MouseEvent.js
+++ b/src/ui/MouseEvent.js
@@ -24,7 +24,7 @@
  */
 var MouseEvent = this.MouseEvent = Event.extend(/** @lends MouseEvent# */{
 	initialize: function(type, event, point, target, delta) {
-		this.base(event);
+		Event.call(this, event);
 		this.type = type;
 		this.point = point;
 		this.target = target;