AutoMapper failing to map a simple list

I have used automapper for mapping lists in the past, for for some reason it won't work in this case.

     public class MyType1 {
            public int Id { get; set; }
            public string Description { get; set; }
        }


        public class MyType2 {
            public int Id { get; set; }
            public stri开发者_JS百科ng Description { get; set; }
        }

     public void DoTheMap() {
                Mapper.CreateMap<MyType2, MyType1>();
                Mapper.AssertConfigurationIsValid();

                var theDto1 = new MyType2() { Id = 1, Description = "desc" };
                var theDto2 = new MyType2() { Id = 2, Description = "desc2" };
                List<MyType2> type2List = new List<MyType2> { theDto1, theDto2 };

                List<MyType1> type1List = Mapper.DynamicMap<List<MyType1>>(type2List);
    //FAILURE.  NO EXCEPTION, BUT ZERO VALUES

                List<MyType1> type1List2 =type2List.Select(Mapper.DynamicMap<MyType1>).ToList();
   //SUCCESS, WITH LINQ SELECT
        }

Change this:

Mapper.DynamicMap<List<MyType1>>(type2List)

To this:

Mapper.Map<List<MyType1>, List<MyType2>>(type2List);

DynamicMap is only if you don't know the type at compile time - for things like anonymous types.