gistfile1.cs

using System;
using System.Collections.Generic;
using System.Reflection;

class Program
{
    static void Main()
    {
        var allocate = typeof(RuntimeTypeHandle).GetMethod("Allocate", (BindingFlags)40);
        var open = allocate.Invoke(null, new[] { typeof(IList<>) });
        Console.WriteLine(open.GetType());
    }
}