Unity Editor can't find IEnumerated

Hey, I have the following Problem:
I want to add a delay to my script. For this I want to use a IEnumerated Method. But Monodevelope doesn’t recognize IEnumerated (marked red) and I get the folowing Error code:

Assets/Scripts/GameManager.cs(28,9): error CS0246: The type or namespace name `IEnumerated’ could not be found. Are you missing an assembly reference?

This is my script:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class GameManager : MonoBehaviour {

	public Transform thePlatformGenerator;
	private Vector3 theplatformGeneratorStartPoint;

	public Transform thePlayer;
	private Vector3 thePlayerStartPoint;

	private PlatformDestructor[] platformList;


	// Use this for initialization
	void Start () {
		theplatformGeneratorStartPoint = thePlatformGenerator.position;
		thePlayerStartPoint = thePlayer.position;
		
	}
	
	// Update is called once per frame
	void Update () {
		
	}

	public void RestartGame(){
		StartCoroutine ("RestartGameCo");
	}

	public IEnumerated RestartGameCo(){
		yield return WaitForSeconds (1.0f);
		thePlayer.position = thePlayerStartPoint;
		thePlatformGenerator.position = theplatformGeneratorStartPoint;
		platformList = FindObjectsOfType<PlatformDestructor> ();
		for (int x = 0; x < 100; x++) {
			Destroy(platformList[x].gameObject);
		}
	}


}

Can anyone help my to fix the Problem?

The coroutine should be of type IEnumerator.

I still get the same Error.