Add a single song to the playlist?

Maybe im missing something obvious but tonight I wanted to add just a single song from an album to the playlist when I made a discovery. I couldnt. There is an "add all" link at the top, but no "add" button next to the songs. Theres a play, but I didnt want to replace my whole playlist with that one song, I wanted to add it at the bottom.
Am I missing something?
Oh and this thing ROCKS. Thank you so much for an amazing piece of work!
Am I missing something?
Oh and this thing ROCKS. Thank you so much for an amazing piece of work!