Cranium of the Common Mudpuppy (Dorsal View)
The Common Mudpuppy (Necturus maculosus) is a species of aquatic salamander found throughout the northeastern United States, and parts of Canada. Pictured here is the dorsal view of the cranium.
Encyclopaedia Britannica (11th ed., vol. 3) (New York, NY: The Encyclopaedia Britannica Company, 1910)