Dawson inferred that "Bathygnathus" was a fast-moving carnivore, reasoning that its deep skull was similar to the short skulls of fast-moving snakes and unlike the long skulls of slow-moving crocodilians. Local naturalist Francis Bain popularized the image of "Bathygnathus" as a dinosaur in the late 1800s, describing it as a "deep jawed monster" that could attack prey "with a bound of sixteen or eighteen feet... bearing it to the ground with its great weight, while the powerful claws prevented its escape, and the sabre-armed jaws completed the sanguinary work of destruction."