NATIVE LEGENDS - ATOSIS THE SERPENT
"Kci-Athussos is an underwater horned serpent, common to the legends of most Algonquian tribes. It is said lurks at the bottom of lakes and feeds on humans. It's Maliseet-Passamaquoddy name literally means Great Serpent; Athussos or Atosis means "serpent."
There are many different stories and versions of legends about the Serpent, most of which are gory in their detail. References are included with this resource file