Create a list of all classes in namespace using reflection and cast to their real type

I have an abstract class Device. A number of classes derive from it, which represent specific devices. So we have, e.g. class RedDevice : Device, class BlueDevice : Device, etc. They are all stored under the Foo.Devices namespace. Here's an overview of the structure:

- Foo
|  ↳ Devices (folder)
|  |   ↳ RedDevice
|  |   ↳ BlueDevice
|  ↳ Device

I want to read create a list with all devices under Foo.Devices, cast to their parent class Device. I can get a list of Types using the following code:

List<System.Type> deviceTypes = 
    Assembly.GetExecutingAssembly().GetTypes().Where(t => t.Namespace == 
    typeof(RedDevice).Namespace).ToList();

But how can I cast them to Device? Direct cast isn't allowed by the compiler and everything else throws wrong type exceptions. Thanks!