function admin_bar_button($wp_admin_bar) {
	$args = array(
		'id' => 'admin-bar-button',
		'title' => 'Custom Menu Options',
		'href' => get_bloginfo('url') . '/wp-admin/themes.php?',
		'meta' => array(
		'class' => 'admin-bar-button')	
	);
	$wp_admin_bar->add_node($args);
}
add_action('admin_bar_menu', 'admin_bar_button', 50);