X 04: Mandible.

Unnecessary text reads:

Mystery jaw, Sedili Besar beach, 25.02.2010. Also a quantity of ribs & half of pelvis (?), not collected.

20.02.10: Mystery jaw belongs to dugong, as voiced by K. Chen & confirmed by internet archival research, blah blah blah blah blah academia

Mandible was quite large indeed.
First sketch of skchbk X.