diff --git a/src/browser/__tests__/ReactDOM-test.js b/src/browser/__tests__/ReactDOM-test.js
index b839089d2b..64328ee179 100644
--- a/src/browser/__tests__/ReactDOM-test.js
+++ b/src/browser/__tests__/ReactDOM-test.js
@@ -15,7 +15,6 @@
 
 var React = require('React');
 var ReactDOM = require('ReactDOM');
-var ReactMount = require('ReactMount');
 var ReactTestUtils = require('ReactTestUtils');
 var div = React.createFactory('div');
 
@@ -53,7 +52,7 @@ describe('ReactDOM', function() {
     var argDiv = ReactTestUtils.renderIntoDocument(
       div(null, 'child')
     );
-    var argNode = ReactMount.getNode(argDiv._rootNodeID);
+    var argNode = argDiv.getDOMNode();
     expect(argNode.innerHTML).toBe('child');
   });
 
@@ -61,7 +60,7 @@ describe('ReactDOM', function() {
     var conflictDiv = ReactTestUtils.renderIntoDocument(
       div({children: 'fakechild'}, 'child')
     );
-    var conflictNode = ReactMount.getNode(conflictDiv._rootNodeID);
+    var conflictNode = conflictDiv.getDOMNode();
     expect(conflictNode.innerHTML).toBe('child');
   });
 
@@ -103,7 +102,7 @@ describe('ReactDOM', function() {
         theBird: <div className="bird" />
       }
     });
-    var root = ReactMount.getNode(myDiv._rootNodeID);
+    var root = myDiv.getDOMNode();
     var dog = root.childNodes[0];
     expect(dog.className).toBe('bigdog');
   });
diff --git a/src/browser/ui/ReactDOMComponent.js b/src/browser/ui/ReactDOMComponent.js
index 3f57ec4f92..71f752e9e5 100644
--- a/src/browser/ui/ReactDOMComponent.js
+++ b/src/browser/ui/ReactDOMComponent.js
@@ -15,7 +15,6 @@
 var CSSPropertyOperations = require('CSSPropertyOperations');
 var DOMProperty = require('DOMProperty');
 var DOMPropertyOperations = require('DOMPropertyOperations');
-var ReactBrowserComponentMixin = require('ReactBrowserComponentMixin');
 var ReactComponent = require('ReactComponent');
 var ReactBrowserEventEmitter = require('ReactBrowserEventEmitter');
 var ReactMount = require('ReactMount');
@@ -148,7 +147,6 @@ function validateDangerousTag(tag) {
 function ReactDOMComponent(tag) {
   validateDangerousTag(tag);
   this._tag = tag;
-  this.tagName = tag.toUpperCase();
 }
 
 ReactDOMComponent.displayName = 'ReactDOMComponent';
@@ -488,8 +486,7 @@ assign(
   ReactDOMComponent.prototype,
   ReactComponent.Mixin,
   ReactDOMComponent.Mixin,
-  ReactMultiChild.Mixin,
-  ReactBrowserComponentMixin
+  ReactMultiChild.Mixin
 );
 
 module.exports = ReactDOMComponent;
diff --git a/src/browser/ui/ReactMount.js b/src/browser/ui/ReactMount.js
index 7124d59e3f..a6f7425654 100644
--- a/src/browser/ui/ReactMount.js
+++ b/src/browser/ui/ReactMount.js
@@ -135,13 +135,7 @@ function getNode(id) {
  * @internal
  */
 function getNodeFromInstance(instance) {
-  // This instance can currently be either a public or private instance since
-  // native nodes are still public.
-  var id = instance._rootNodeID;
-  // TODO: Once these are only public instances, remove this conditional.
-  if (id == null) {
-    id = ReactInstanceMap.get(instance)._rootNodeID;
-  }
+  var id = ReactInstanceMap.get(instance)._rootNodeID;
   if (ReactEmptyComponent.isNullComponentID(id)) {
     return null;
   }
diff --git a/src/browser/ui/dom/components/ReactDOMButton.js b/src/browser/ui/dom/components/ReactDOMButton.js
index a5fd34caf6..79206afe9f 100644
--- a/src/browser/ui/dom/components/ReactDOMButton.js
+++ b/src/browser/ui/dom/components/ReactDOMButton.js
@@ -39,6 +39,7 @@ var mouseListenerNames = keyMirror({
  */
 var ReactDOMButton = ReactClass.createClass({
   displayName: 'ReactDOMButton',
+  tagName: 'BUTTON',
 
   mixins: [AutoFocusMixin, ReactBrowserComponentMixin],
 
diff --git a/src/browser/ui/dom/components/ReactDOMForm.js b/src/browser/ui/dom/components/ReactDOMForm.js
index 8af4a2e7b1..20c2b038cc 100644
--- a/src/browser/ui/dom/components/ReactDOMForm.js
+++ b/src/browser/ui/dom/components/ReactDOMForm.js
@@ -27,6 +27,7 @@ var form = ReactElement.createFactory('form');
  */
 var ReactDOMForm = ReactClass.createClass({
   displayName: 'ReactDOMForm',
+  tagName: 'FORM',
 
   mixins: [ReactBrowserComponentMixin, LocalEventTrapMixin],
 
diff --git a/src/browser/ui/dom/components/ReactDOMInput.js b/src/browser/ui/dom/components/ReactDOMInput.js
index cf3758e55a..50026420a6 100644
--- a/src/browser/ui/dom/components/ReactDOMInput.js
+++ b/src/browser/ui/dom/components/ReactDOMInput.js
@@ -52,6 +52,7 @@ function forceUpdateIfMounted() {
  */
 var ReactDOMInput = ReactClass.createClass({
   displayName: 'ReactDOMInput',
+  tagName: 'INPUT',
 
   mixins: [AutoFocusMixin, LinkedValueUtils.Mixin, ReactBrowserComponentMixin],
 
diff --git a/src/browser/ui/dom/components/ReactDOMOption.js b/src/browser/ui/dom/components/ReactDOMOption.js
index 4faa788fb4..1657703e31 100644
--- a/src/browser/ui/dom/components/ReactDOMOption.js
+++ b/src/browser/ui/dom/components/ReactDOMOption.js
@@ -24,6 +24,7 @@ var option = ReactElement.createFactory('option');
  */
 var ReactDOMOption = ReactClass.createClass({
   displayName: 'ReactDOMOption',
+  tagName: 'OPTION',
 
   mixins: [ReactBrowserComponentMixin],
 
diff --git a/src/browser/ui/dom/components/ReactDOMSelect.js b/src/browser/ui/dom/components/ReactDOMSelect.js
index 051a9759d6..e1ac3d68d9 100644
--- a/src/browser/ui/dom/components/ReactDOMSelect.js
+++ b/src/browser/ui/dom/components/ReactDOMSelect.js
@@ -109,6 +109,7 @@ function updateOptions(component, propValue) {
  */
 var ReactDOMSelect = ReactClass.createClass({
   displayName: 'ReactDOMSelect',
+  tagName: 'SELECT',
 
   mixins: [AutoFocusMixin, LinkedValueUtils.Mixin, ReactBrowserComponentMixin],
 
diff --git a/src/browser/ui/dom/components/ReactDOMTextarea.js b/src/browser/ui/dom/components/ReactDOMTextarea.js
index 765d023652..e0f7afee60 100644
--- a/src/browser/ui/dom/components/ReactDOMTextarea.js
+++ b/src/browser/ui/dom/components/ReactDOMTextarea.js
@@ -50,6 +50,7 @@ function forceUpdateIfMounted() {
  */
 var ReactDOMTextarea = ReactClass.createClass({
   displayName: 'ReactDOMTextarea',
+  tagName: 'TEXTAREA',
 
   mixins: [AutoFocusMixin, LinkedValueUtils.Mixin, ReactBrowserComponentMixin],
 
diff --git a/src/core/ReactComponent.js b/src/core/ReactComponent.js
index ffc8334408..564c7311cc 100644
--- a/src/core/ReactComponent.js
+++ b/src/core/ReactComponent.js
@@ -453,7 +453,11 @@ var ReactComponent = {
      * @internal
      */
     getPublicInstance: function() {
-      return this;
+      invariant(
+        false,
+        'getPublicInstance should never be called on the base class. It must ' +
+        'be overriden.'
+      );
     }
   }
 };
diff --git a/src/core/ReactNativeComponent.js b/src/core/ReactNativeComponent.js
index 9f4be86474..3f03fa1c51 100644
--- a/src/core/ReactNativeComponent.js
+++ b/src/core/ReactNativeComponent.js
@@ -11,6 +11,9 @@
 
 "use strict";
 
+var ReactClass = require('ReactClass');
+var ReactElement = require('ReactElement');
+
 var assign = require('Object.assign');
 var invariant = require('invariant');
 
@@ -37,6 +40,22 @@ var ReactNativeComponentInjection = {
   }
 };
 
+function autoGenerateWrapperClass(type) {
+  return ReactClass.createClass({
+    tagName: type.toUpperCase(),
+    render: function() {
+      return new ReactElement(
+        type,
+        null,
+        null,
+        null,
+        null,
+        this.props
+      );
+    }
+  });
+}
+
 /**
  * Create an internal class for a specific tag.
  *
@@ -47,12 +66,7 @@ var ReactNativeComponentInjection = {
 function createInstanceForTag(tag, props, parentType) {
   var componentClass = tagToComponentClass[tag];
   if (componentClass == null) {
-    invariant(
-      genericComponentClass,
-      'There is no registered component for the tag %s',
-      tag
-    );
-    return new genericComponentClass(tag, props);
+    tagToComponentClass[tag] = componentClass = autoGenerateWrapperClass(tag);
   }
   if (parentType === tag) {
     // Avoid recursion
diff --git a/src/core/__tests__/ReactComponent-test.js b/src/core/__tests__/ReactComponent-test.js
index 35e7ada062..3b09fb2f52 100644
--- a/src/core/__tests__/ReactComponent-test.js
+++ b/src/core/__tests__/ReactComponent-test.js
@@ -26,10 +26,6 @@ describe('ReactComponent', function() {
     reactComponentExpect = require('reactComponentExpect');
 
     getMountDepth = function(instance) {
-      if (instance.mountComponent) {
-        // Native instance
-        return instance._mountDepth;
-      }
       return ReactInstanceMap.get(instance)._mountDepth;
     };
   });
@@ -306,9 +302,9 @@ describe('ReactComponent', function() {
     expect(getMountDepth(root)).toBe(0);
     expect(getMountDepth(root.refs.switcher)).toBe(1);
     expect(getMountDepth(root.refs.switcher.refs.box)).toBe(2);
-    expect(getMountDepth(root.refs.switcher.refs.switcherDiv)).toBe(4);
-    expect(getMountDepth(root.refs.child)).toBe(5);
+    expect(getMountDepth(root.refs.switcher.refs.switcherDiv)).toBe(5);
+    expect(getMountDepth(root.refs.child)).toBe(7);
     expect(getMountDepth(root.refs.switcher.refs.box.refs.boxDiv)).toBe(3);
-    expect(getMountDepth(root.refs.child.refs.span)).toBe(6);
+    expect(getMountDepth(root.refs.child.refs.span)).toBe(8);
   });
 });
diff --git a/src/core/__tests__/ReactCompositeComponent-test.js b/src/core/__tests__/ReactCompositeComponent-test.js
index ef7f503a87..9c4a4c0722 100644
--- a/src/core/__tests__/ReactCompositeComponent-test.js
+++ b/src/core/__tests__/ReactCompositeComponent-test.js
@@ -66,8 +66,8 @@ describe('ReactCompositeComponent', function() {
      * reallocated again.
      */
     ChildUpdates = React.createClass({
-      getAnchorID: function() {
-        return this.refs.anch._rootNodeID;
+      getAnchor: function() {
+        return this.refs.anch;
       },
       render: function() {
         var className = cx({'anchorClass': this.props.anchorClassOn});
@@ -182,8 +182,8 @@ describe('ReactCompositeComponent', function() {
     instance.setProps({renderAnchor: false});  // Clear out the anchor
     // rerender
     instance.setProps({renderAnchor: true, anchorClassOn: false});
-    var anchorID = instance.getAnchorID();
-    var actualDOMAnchorNode = ReactMount.getNode(anchorID);
+    var anchor = instance.getAnchor();
+    var actualDOMAnchorNode = anchor.getDOMNode();
     expect(actualDOMAnchorNode.className).toBe('');
   });
 
@@ -779,9 +779,11 @@ describe('ReactCompositeComponent', function() {
     React.unmountComponentAtNode(container);
     expect(innerUnmounted).toBe(true);
 
-    // <Component />, <Inner />, and both <div /> elements each call
-    // unmountIDFromEnvironment which calls purgeID, for a total of 4.
-    expect(ReactMount.purgeID.callCount).toBe(4);
+    // <Component />, <Inner />, and both <div /> elements and their wrappers
+    // each call unmountIDFromEnvironment which calls purgeID, for a total of 6.
+    // TODO: Test the effect of this. E.g. does the node cache get repopulated
+    // after a getDOMNode call?
+    expect(ReactMount.purgeID.callCount).toBe(6);
   });
 
   it('should warn when shouldComponentUpdate() returns undefined', function() {
diff --git a/src/core/__tests__/ReactCompositeComponentError-test.js b/src/core/__tests__/ReactCompositeComponentError-test.js
index 865b76733e..130bbf70bb 100644
--- a/src/core/__tests__/ReactCompositeComponentError-test.js
+++ b/src/core/__tests__/ReactCompositeComponentError-test.js
@@ -26,8 +26,8 @@ describe('ReactCompositeComponent-error', function() {
       }
     });
 
-    var instance = <Component />;
-    instance = ReactTestUtils.renderIntoDocument(instance);
+    new Component();
+
     expect(ReactErrorUtils.guard.mostRecentCall.args[1])
       .toEqual('Component.someHandler');
   });
diff --git a/src/core/__tests__/ReactInstanceHandles-test.js b/src/core/__tests__/ReactInstanceHandles-test.js
index 0620b40d21..bf2a71def6 100644
--- a/src/core/__tests__/ReactInstanceHandles-test.js
+++ b/src/core/__tests__/ReactInstanceHandles-test.js
@@ -12,6 +12,7 @@
 "use strict";
 
 var React = require('React');
+var ReactInstanceMap = require('ReactInstanceMap');
 var ReactTestUtils = require('ReactTestUtils');
 var ReactMount = require('ReactMount');
 
@@ -66,8 +67,7 @@ describe('ReactInstanceHandles', function() {
     if (instance === null) {
       return '';
     }
-    var internal = ReactTestUtils.getInternalRepresentation(instance);
-    return internal._rootNodeID;
+    return ReactInstanceMap.get(instance)._rootNodeID;
   }
 
   beforeEach(function() {
diff --git a/src/core/__tests__/ReactMultiChildReconcile-test.js b/src/core/__tests__/ReactMultiChildReconcile-test.js
index faa9d467ef..a56075fc5e 100644
--- a/src/core/__tests__/ReactMultiChildReconcile-test.js
+++ b/src/core/__tests__/ReactMultiChildReconcile-test.js
@@ -87,7 +87,10 @@ var FriendsStatusDisplay = React.createClass({
     // TODO: Update this to a better test that doesn't rely so much on internal
     // implementation details.
     var statusDisplays =
-      ReactInstanceMap.get(this)._renderedComponent._renderedChildren;
+      ReactInstanceMap.get(this)
+      ._renderedComponent
+      ._renderedComponent
+      ._renderedChildren;
     for (name in statusDisplays) {
       var child = statusDisplays[name];
       var isPresent = !!child;
diff --git a/src/test/ReactTestUtils.js b/src/test/ReactTestUtils.js
index 291b2920ea..0527174f1e 100644
--- a/src/test/ReactTestUtils.js
+++ b/src/test/ReactTestUtils.js
@@ -99,14 +99,6 @@ var ReactTestUtils = {
              (inst.constructor === type));
   },
 
-  getInternalRepresentation: function(inst) {
-    // TODO: Remove this duck check once we have a separate DOM/Native instance
-    if (typeof inst.mountComponent === 'function') {
-      return inst;
-    }
-    return ReactInstanceMap.get(inst);
-  },
-
   getRenderedChildOfCompositeComponent: function(inst) {
     if (!ReactTestUtils.isCompositeComponent(inst)) {
       return null;
@@ -121,7 +113,10 @@ var ReactTestUtils = {
     }
     var ret = test(inst) ? [inst] : [];
     if (ReactTestUtils.isDOMComponent(inst)) {
-      var renderedChildren = inst._renderedChildren;
+      var internalInstance = ReactInstanceMap.get(inst);
+      var renderedChildren = internalInstance
+        ._renderedComponent
+        ._renderedChildren;
       var key;
       for (key in renderedChildren) {
         if (!renderedChildren.hasOwnProperty(key)) {
diff --git a/src/test/reactComponentExpect.js b/src/test/reactComponentExpect.js
index a0638996c4..d92f985d1f 100644
--- a/src/test/reactComponentExpect.js
+++ b/src/test/reactComponentExpect.js
@@ -12,6 +12,7 @@
 
 "use strict";
 
+var ReactInstanceMap = require('ReactInstanceMap');
 var ReactTestUtils = require('ReactTestUtils');
 
 var assign = require('Object.assign');
@@ -27,14 +28,20 @@ function reactComponentExpect(instance) {
 
   expect(instance).not.toBeNull();
 
-  this._instance = ReactTestUtils.getInternalRepresentation(instance);
+  var internalInstance = ReactInstanceMap.get(instance);
 
-  expect(typeof instance).toBe('object');
-  expect(typeof instance.constructor).toBe('function');
-  expect(ReactTestUtils.isElement(instance)).toBe(false);
+  expect(typeof internalInstance).toBe('object');
+  expect(typeof internalInstance.constructor).toBe('function');
+  expect(ReactTestUtils.isElement(internalInstance)).toBe(false);
+
+  return new reactComponentExpectInternal(internalInstance);
 }
 
-assign(reactComponentExpect.prototype, {
+function reactComponentExpectInternal(internalInstance) {
+  this._instance = internalInstance;
+}
+
+assign(reactComponentExpectInternal.prototype, {
   // Getters -------------------------------------------------------------------
 
   /**
@@ -62,7 +69,7 @@ assign(reactComponentExpect.prototype, {
     this.toBeCompositeComponent();
     var child = this._instance._renderedComponent;
     // TODO: Hide ReactEmptyComponent instances here?
-    return new reactComponentExpect(child);
+    return new reactComponentExpectInternal(child);
   },
 
   /**
@@ -72,14 +79,15 @@ assign(reactComponentExpect.prototype, {
     // Currently only dom components have arrays of children, but that will
     // change soon.
     this.toBeDOMComponent();
-    var renderedChildren = this._instance._renderedChildren || {};
+    var renderedChildren =
+      this._instance._renderedComponent._renderedChildren || {};
     for (var name in renderedChildren) {
       if (!renderedChildren.hasOwnProperty(name)) {
         continue;
       }
       if (renderedChildren[name]) {
         if (renderedChildren[name]._mountIndex === childIndex) {
-          return new reactComponentExpect(renderedChildren[name]);
+          return new reactComponentExpectInternal(renderedChildren[name]);
         }
       }
     }
@@ -88,15 +96,16 @@ assign(reactComponentExpect.prototype, {
 
   toBeDOMComponentWithChildCount: function(n) {
     this.toBeDOMComponent();
-    expect(this._instance._renderedChildren).toBeTruthy();
-    var len = Object.keys(this._instance._renderedChildren).length;
+    expect(this._instance._renderedComponent._renderedChildren).toBeTruthy();
+    var len = Object.keys(this._instance._renderedComponent._renderedChildren)
+              .length;
     expect(len).toBe(n);
     return this;
   },
 
   toBeDOMComponentWithNoChildren: function() {
     this.toBeDOMComponent();
-    expect(this._instance._renderedChildren).toBeFalsy();
+    expect(this._instance._renderedComponent._renderedChildren).toBeFalsy();
     return this;
   },