I have a web service containing many different layers, organized in a group structure. It appears that the groups also have indices, and so I thought that I would be able to add the URL to the group layer and have all of its sublayers show up, but none of them do.

As seen above, I tried to add the URL to the "Agriculture" group (.../MapServer/14), but nothing shows up on the map when I do. Is there some kind of special trick to this or is it simply not possible?