Kellogg, W. N., & Pomeroy, W. B. (1936). Maze learning in water snakes. Journal of Comparative Psychology, 21(3), 275-295.
http://dx.doi.org/10.1037/h0063023
12 water snakes were trained to traverse a T-maze containing two blind alleys. The incentive was escape from cold water; there was warm water in the home compartment. Typical learning curves for time and errors were obtained. There is some indication that shedding, which necessitated interruptions in the training, produces some physiological change which interferes with learning. "Vision was apparently of considerably less importance than the ability of a snake to 'feel' its way through the maze by pushing against the sides with its nose." (PsycINFO Database Record (c) 2016 APA, all rights reserved)