Selectで実行時エラー

gistfile1.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Linqメソッドで遊ぶ
{
	class Program
	{
		static void Main(string[] args)
		{
			var list = new List<Hoge>(){new inheritHoge1() { a = "hoge1" },
										new inheritHoge2() { a = "hoge2" }};

			var p = list.Select(x => (inheritHoge1)x);
			foreach (var item in p)
			{
				Console.WriteLine(item.a);
			}
			Console.Read();
		}
	}

	class Hoge
	{
		public string a = string.Empty;
	}

	class inheritHoge1 : Hoge
	{
	}

	class inheritHoge2 : Hoge
	{
	}
}