Cullum of Celdon tells you, "Ah, here to prove yourself to the Society, are you? I commend you for your pro-active nature. You can help me, and earn yourself some rewards, by venturing into the Graveyard in the Direlands and bringing me eight jawbones. I seek a special kind of jawbone. You can't just dig up a skull and bring me a bone."
Cullum of Celdon tells you, "The only jawbones that I would find useful are the ones from magically enchanted skeletons: Pyre Minions, Pyre Skeletons, and Pyre Champions carry the kinds of bones I need. Be on your way, and come talk to me when you have eight!"