The eel is a long, thin bony fish of the order Anguilliformes. Because fishermen never caught anything they recognized as young eels, the life cycle of the eel was a mystery for a very long period of scientific history. Although more than 6500 publications mention eels, much of their life history remains an enigma. Other early scientists believed that the eelpout Zoarces viviparus was the "mother of eels" (the translation of the German name "Aalmutter").