Studies from old photos that I took at the Natural History Museum in D.C. on my birthday in 2005. There are a Basilosaurus, a Dolichorhynchops (the plesiosaurid), and a…turtle. Of some kind. Sorry, I got lucky with the second one, as the Wiki page on Plesiosauroidea has a picture of the same skeleton. The Smithsonian hasn’t done a great job at making it easy to look this stuff up.

AH! Protostega. That’s it. A lot of the critters from that exhibit apparently came from the Niobrara Formation.

“Toto, I’ve a feeling we’re not in Kansas anymore.”

This scene represents a moment in time 83 million years ago, in what is now the state of Kansas, which was covered by a body of water known as the Western Interior Seaway and populated by diverse, prehistoric marine life. In this diorama near Dinosaurs in Their Time, an agile marine reptile, Dolichorhynchops bonneri, dives after the penguin-like bird, Hesperornis regalis.