I thought it would be cool to see what members here at UM have come across.
I live in Cleburne, Texas, which some of you may know is only a few miles from Glen Rose. Glen Rose is the city in which many dinosaur fossils and tracks have been found, and it is in a rock shipment from that town that I found the most incredible thing ever: A two foot Mosasaur Skull. You may also know that Texas used to be underwater, hence the discovery of fosilized shells, fish, and larger sea predators... Unfortunately, I found the skull on my father's boss' property, so it belongs to him... And since the two of them have since parted ways in a nasty fashion, I doubt I'll ever get to see it again.
I work at GameStop here in the States and have had the pleasure of meeting a few interesting people. Luckily, one of them happened to be a palaeontologist. I gave him a few snapshots, and he's the one who returned several days after consulting his coleagues declaring it a mosasaur. The mosasaur is considered by many to be T-REX of the ocean, although you Megladon buffs out there might disagree.
I do not have a picture of the one I found because I am currently without a scanner, but in case you are wondering, below are a few pictures of a Mosasaur skull/tooth/what it may have looked like/etc.
So, what have you found, and where?

