Walter Henry "Doc" Snell (May 19, 1889 – July 23, 1980) was a pinch-hitter/catcher in Major League Baseball who played briefly for the Boston Red Sox during the 1913 season. Following this brief baseball career he became a successful mycologist who worked primarily at Brown University for the next 60 years.

In 1913, he was signed by the Philadelphia Athletics owner Connie Mack, but broke his hand in a game at Brown and was dealt to the Red Sox.

In a six-game career, Snell was a .250 hitter (3-for-12) with one run and one stolen base without RBI or home runs. In two catching appearances, he committed one error in 13 chances accepted for a .923 fielding percentage. Snell hit a single in his first major league at bat off Cleveland Naps pitcher Nick Cullop on August 1, 1913. He was one of five catchers the Red Sox used during the 1913 season.

Following his majors career, Snell continued to play some minor league baseball while studying for his master's degree, playing in 1914 and 1915 in the International League with the Toronto Maple Leafs (1914) and Rochester Hustlers (1915), and for the Manchester team of the New England League (1915), becoming a first baseman in his last baseball season.

After receiving his master's degree from Brown in 1915, Snell earned a Ph.D. degree in botany. In the summer of 1923, he managed the Hyannis town team in the Cape Cod Baseball League.^[1][2] Before teaching at Brown, Snell worked for the Bureau of Plant Industry between 1918 and 1920. At Brown, Snell served as an Assistant Professor from 1920–21, an Associate Professor from 1921–42, the Stephen T. Olney Professor of Botany from 1942–45, and Professor of Natural History from 1945–59. Snell focused primarily in mycology. He discovered several forms of mushrooms in the Northeast which were previously thought not to grow there and published multiple mycological works. In 1970, he and his wife co-wrote The Boleti of Northeastern North America which was the culmination of his life's work; it contained hundreds of his watercolor illustrations of fungi.^[3]

Snell married twice. His second wife, Esther A. Dick (later Esther Dick Snell), was a fellow mycologist who co-wrote A Glossary of the Fungi with him, among other works.^[5]

Snell died at the age of 91 in Providence, Rhode Island.