namespace ValueTypes
{
    public class ValueBase { }
}

public class EnumBase
{
    protected IList<ValueTypes.ValueBase> values;
}

public class EnumBase<EntryType> : EnumBase
    where EntryType : ValueTypes.ValueBase
{
    private LinkedList<EntryType> valuesInternal;

    public EnumBase() : base()
    {
        valuesInternal = new LinkedList<EntryType>();
        values = new List<ValueTypes.ValueBase>(valuesInternal);
    }
}