Arizonasaurus' sail is strange to me. It doesn't really rise until it gets past the shoulderblades, giving it a somewhat abbreviated appearance. This is in contrast to animals like Dimetrodon and Ouranosaurus, who have sails that begin at or cranially to the scapulae. Arizonasaurus also has unusually flared neural spines, meaning that there wasn't a whole lot of skin between the vertebrae of the sail. Again, this is unlike Dimetrodon and Edaphosaurus, who had spike-like neural spines. Many other sailbacked tetrapods had flared neural spines though, including Platyhystrix (an amphibian) and Spinosaurus. One wonders if there was a functional difference between these constructions, or just different ways of building the same structure?
For more Virtual Art Show fun, click the "Virtual Art Show" tag, because I'm too lazy to link to all the individual entries. Scott has several of his own pieces up at Coherent Lighthouse, too, so be sure to check those out! And Raven--all you've gotta do is Tupandactylus! Get on it!