Puzzling It Out

Yesterday, Miles and I were looking at a set of animal/alphabet "flashcards."  Miles was flying through the cards, rattling off the names of the animals... alligator, beaver, cow..., until he got to the "N" animal.  Here's what he saw. 

He analyzed the card while scowling, trying figure out what "N" animal it could possibly be.  Finally he looked up and pronounced the animal a "Nizard" and continued on.