A public relations coordinator for a Texas museum recently spotted the fossilized bones of a 75-million-year-old duckbilled dinosaur while taking a tour of the area where a mummified duckbill was found eight years ago.

The mummified brachylophosaurus, nicknamed Leonardo, is on loan to the Houston Museum of Natural Science.

Museum employees were in Montana two weeks ago on a tour of the area where Leonardo was found when Steven Cowan, 22, thought he saw bones sticking out of a rock outcropping on a hillside.

"It was exciting," said Cowan.

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Paleontologist Mark Thompson "said they appeared to be ribs. He came back and found a scapula [shoulder bone] and a few other tendons showing from the rock."

"About 10 feet away, we found another bone jutting out of the rock," Cowan said. "Based on the position, the head may have fallen off and rolled down the hill, but we're hoping that the legs and torso are still in the stone."

Bob Bakker, paleo curator at the Houston Museum, said he likely wouldn't have found the specimen that Cowan nicknamed Marco.

"One of the things we always need to watch out for is thinking that we know it all," Bakker said. "I knew enough never to go to a ridge top because you don't find specimens there. But I forgot to tell that to Steven, so he did exactly that and proved me wrong."

Cowan spotted the fossil later in the afternoon on a rainy day. Thompson said he was already walking back to the truck.

"I really didn't want to walk half a mile back to see it, but I did," said Thompson. "And I saw some tendons, vertebrae, ribs and a shoulder blade."