Northern water snake The belly also varies in color. It can be white, yellow, or gray. Usually it also has reddish or black crescents. The northern water snake is nonvenomous and harmless to humans, but superficially resembles the venomous cottonmouth and is often killed unnecessarily as a result of this mistaken identity. The two can be easily distinguished by morphological traits: the water snake has a longer, more slender body and a flattened head the same width as the neck, round pupils, and no heat-sensing pits. The cottonmouth has a fatter body, a wedge-shaped head with prominent venom glands that are wider than
U. S. R. Murty of the Journal of Combinatorial Theory, Series B. U. S. R. Murty Uppaluri Siva Ramachandra Murty, or U. S. R. Murty (as he prefers to write his name), is a Professor Emeritus of the Department of Combinatorics and Optimization, University of Waterloo. U. S. R. Murty received his Ph.D. in 1967 from the Indian Statistical Institute, Calcutta, with a thesis on extremal graph theory; his advisor was C. R. Rao. Murty is well known for his work in matroid theory and graph theory, and mainly for being a co-author with J. A. Bondy of a textbook on graph theory. Murty