Why Cant I Put Stuff In My Inspector

Trying to make a game and I scripted in a slot for a particle emitter. I followed a guide and when i was finished, I realized that there is no particle emitter in unity 4, only particle system. Can someone help me with this problem. My Script Is:
using UnityEngine;
using System.Collections;

public class Player_Status_Controller : MonoBehaviour {

public int Lives = 5;
public ParticleEmitter EnemyExplosionEffect;

public void OnGUI() {
	GUI.Label(new Rect(20, 20, 100, 20), System.String.Format("LIVES: {0}", Lives));
}

public void OnTriggerEnter(Collider collider) {
	Lives--;
	
	Vector3 enemy_postion = collider.transform.position;
	Destroy(collider.gameObject);
	
	ParticleEmitter explosion = (ParticleEmitter)Instantiate(EnemyExplosionEffect, enemy_postion, Quaternion.identity);
	
	explosion.Emit();

}

}

Yes, you can help yourself: Just do what it says and assign the variable. (I’m guessing it’s the ParticleEmitter.)

Double click on the error message in Unity and it will highlight the line the error occurs on in Mono. When posting these kinds of errors please describe the line the error occurs on. In this case @a dog is likely right that the problem is that EnemyExplosionEffect has not been assigned. You need to select the game object this script is attached to in the inspector then drag and drop the game object that has the particle emitter attached onto the EnemyExplosionEffect variable.