How to clear single notifications rather than wiping out the whole list.

The subject lines pretty much says it all. I'd like to keep certain notifications and clear others. For example. I'd like the phone to continue to remind me about a certain email I haven't read, but clear the notifications for apps that have been installed. I can only see an option to clear the whole list of notifications when I pull the list down from the status bar. Am I missing something? I tried long-press, but that just launches the app associated with the notification. I'd like to have a menu item that comes up on long-press to delete the specific notification I'm pointing to.