Unity Layered cast test

using UnityEngine;
using System.Collections;

public class RaycastTest : MonoBehaviour {

        public int LayerIndex = 8;

        void Update()
        {
                if (Input.GetMouseButton(0) )
                {
                        Ray R = Camera.main.ScreenPointToRay (Input.mousePosition);
                        foreach (RaycastHit hitinfo in Physics.RaycastAll(R,10000.0f, LayerIndex ) )
                        {
                                Debug.Log("HIT "+hitinfo.collider.gameObject+" AT LAYER "+LayerIndex);
                        }

                }
                if (Input.GetMouseButton(1) )
                {
                        Ray R = Camera.main.ScreenPointToRay (Input.mousePosition);
                        foreach (RaycastHit hitinfo in Physics.RaycastAll(R,10000.0f ) )
                        {
                                Debug.Log("HIT "+hitinfo.collider.gameObject+" WITH LAYER"+hitinfo.collider.gameObject.layer);
                        }

                }
        }
}