Magento: Get Bundled Items By Bundle Product

 <?php foreach ($collection as $_product){ ?>

 $bundleIds = Mage::getResourceSingleton('bundle/selection')->getParentIdsByChild($productId);

/*************************Bundled product id*******************************/
          $parentid=$bundleIds[0];
       $_newProduct = Mage::getModel('catalog/product')->load($parentid);
 } ?>