Creció en una familia escocesa-irlandesa-británica, con tres hermanos y tres hermanas en la granja Pammell, cerca de Lynchburg, Virginia. Fue curador del New York Botanical Garden (NYBG), Bronx.
Recogió más de 75.000 ejemplares y describió alrededor de 1.700 nuevas especies.
Algunas publicaciones
Murrill realizó 510 publicaciones, incluidos documentos micológicos y de botánica, notas generales, informes varios, revistas, biografías y artículos de divulgación sobre la historia natural.[2]
(1902) "The Polyporaceae of North America: I. The genus Ganoderma" in Bulletin of the Torrey Botanical Club 29:10 pp. 599 - 608
(1903) "The Polyporaceae of North America: II. The genus Pyropolyporus" in Bulletin of the Torrey Botanical Club 30:2 pp. 109 - 120
(1903) "The Polyporaceae of North America: III. The genus Fomes" in Bulletin of the Torrey Botanical Club 30:4 pp. 225 - 232
(1903) "The Polyporaceae of North America: IV. The genus Elfvingia" in Bulletin of the Torrey Botanical Club 30:5 pp. 296 - 301
(1903) "The Polyporaceae of North America: V. The genera Cryptoporus, Piptoporus, Scutiger and Porodiscus" in Bulletin of the Torrey Botanical Club 30:8 pp. 423 - 434
(1904) "The Polyporaceae of North America: VI. The genus Polyporus" in Bulletin of the Torrey Botanical Club 31:1 pp. 29 - 44
(1904) "The Polyporaceae of North America: VIII. Hapalopilus, Pycnoporus and new monotypic genera" in Bulletin of the Torrey Botanical Club 31:8 pp. 415 - 428
(1904) "The Polyporaceae of North America: VII. The genera Hexagona, Grifola, Romellia, Coltricia and Coltriciella" in Bulletin of the Torrey Botanical Club 31:6 pp. 325 - 348
(1904) "A key to the perennial Polyporaceae of temperate North America" in Torreya 4:11 pp. 165 - 167
(1904) "The Polyporaceae of North America: IX. Inonotus, Sesia and monotypic genera" in Bulletin of the Torrey Botanical Club 31:11 pp. 593 - 610
(1905) "The Polyporaceae of North America: XIII. The described species of Bjerkandera, Trametes, and Coriolus" in Bulletin of the Torrey Botanical Club 32:12 pp. 633 - 656
(1905) "The Polyporaceae of North America: X. Agaricus, Lenzites, Cerrena and Favolus" in Bulletin of the Torrey Botanical Club 32:2 pp. 83 - 103
(1905) "The Polyporaceae of North America: XI. A synopsis of the brown pileate species" in Bulletin of the Torrey Botanical Club 32:7 pp. 353 - 371
(1905) "The Polyporaceae of North America: XII. A synopsis of the white and bright-colored pileate species" in Bulletin of the Torrey Botanical Club 32:9 pp. 469 - 493
(1905) "A key to the stipitate Polyporaceae of temperate North America: I." in Torreya 5:2 pp. 28 - 30
(1905) "A key to the stipitate Polyporaceae of temperate North America: II." en Torreya 5:3, pp. 43-44.
(1905) "A key to the Agaricaceae of temperate North America" en Torreya 5:12, pp. 213-214.
(1907-1908) "Polyporaceae" en North American Flora 9, pp. 1-131.
(1908) "A key to the white and bright-colored sessile Polyporeae of temperate North America: 1" en Torreya 8:1, pp. 14-16.
(1908) "A key to the white and bright-colored sessile Polyporeae of temperate North America: 2" in Torreya 8:2 pp. 28 - 29
(1908) "Boleti from western North Carolina" in Torreya 8:9 pp. 209 - 217
(1908) "A key to the white and bright-colored sessile Polyporeae of temperate North America: 3" en Torreya 8:6, pp. 130-132.
(1908) "Collecting and studying Boleti" en Torreya 8:3, pp. 50-55.
(1909) "The Boletaceae of North America: 1." en Mycologia 1:1, pp. 4-18.
(1909) "The Boletaceae of North America: 2." en Mycologia 1:4, pp. 140-160.
(1910 - 1916) "Agaricaceae: Part one" en North American Flora 9, pp. 162-426.
(1910) "Boletaceae" en North American Flora 9 pp. 133 - 161
(1911) "The Agaricaceae of Tropical North America: 2. White-spored genera (cont.)" in Mycologia 3:2 pp. 79 - 91
(1911) "The Agaricaceae of Tropical North America: 4. Genera with rose-colored spores" in Mycologia 3:6 pp. 271 - 282
(1911) "The Agaricaceae of Tropical North America: 1. White-spored genera" in Mycologia 3:1
(1911) "The Agaricaceae of Tropical North America: 3. Still more white-spored genera" in Mycologia 3:4 pp. 189 - 199
(1912) "Illustrations of Fungi: 12" in Mycologia 6 pp. 289 - 293
(1912) "The Agaricaceae of the Pacific Coast: 3. Brown and black-spored genera" in Mycologia 4:6 pp. 294 - 308
(1912) "The Agaricaceae of the Pacific Coast: 1. White-spored genera" in Mycologia 4:4 pp. 205 - 217
(1912) "The Agaricaceae of Tropical North America: 5. Ochre-spored genera" in Mycologia 4:2 pp. 72 - 83
(1912) "The Agaricaceae of the Pacific Coast: 2. White and ochre-spored genera" in Mycologia 4:5 pp. 231 - 262
(1913) "The Agaricaceae of Tropical North America: 6. Ochre-spored genera (cont.)" in Mycologia 5:1 pp. 18 - 36
(1913) "The Amanitas of Eastern United States" in Mycologia 5:2 pp. 72 - 86
(1914) Northern Polypores 64 pp.
(1915) "The genus Clitocybe in North America" in Mycologia 7:5 pp. 256 - 283
(1915) "The validity of Clitocybe megalospora" in Mycologia 7 pp. 157 - 158
(1915) Southern Polypores
(1915) "The genus Lepista" in Mycologia 7:2 pp. 105 - 107
(1915) Tropical Polypores
(1915) Western Polypores
(1916) "Gymnopus" in North American Flora 9:5 pp. 352 - 376
(1918) "The Agaricaceae of Tropical North America: 8. Purple-brown to black-spored genera (cont.)" in Mycologia 10:2 pp. 62 - 85
(1918) "The Agaricaceae of Tropical North America: 7. Purple-brown to black-spored genera" in Mycologia 10:1 pp. 15 - 33
(1919) The Naturalist in a Boarding School
(1919) The Natural History of Staunton Virginia
(1920) "Another new truffle" in Mycologia 12:3 pp. 157 - 158
(1920) "Light-colored resupinate Polypores: 1." in Mycologia 12:2 pp. 77-92.
(1920) "Light-colored resupinate Polypores: 2." in Mycologia 12:6 pp. 299-308.
(1920) "Corrections and additions to the Polypores of temperate North America" in Mycologia 12:1 pp. 6-24.
(1921) "Light-colored resupinate Polypores: 4." in Mycologia 13:3 pp. 171-178.
(1921) "Light-colored resupinate Polypores: 3." in Mycologia 13:2 pp. 83-100.
(1922) "Dark-spored Agarics: 4. Deconica, Atylospora and Psathyrella" in Mycologia 14:5 pp. 258 - 278
(1922) "Dark-spored Agarics: 1. Drosophila, Hypholoma and Pilosace" in Mycologia 14:2 pp. 61 - 76
(1922) "Dark-spored Agarics: 2. Gomphidius and Stropharia" en Mycologia 14:3, pp. 121-142.
(1922) "Dark-spored Agarics: 3. Agaricus" en Mycologia 14:4, pp. 200-221.
(1923) "Dark-spored Agarics: 5. Psilocybe" en Mycologia 15:1, pp. 1-22.
(1938) "New Florida Agarics" en Mycologia 30, pp. 362-364.
(1939) "Fungi" in Bulletin of the Torrey Botanical Club 66, pp. 154-156.
(1940) "Additions to Florida Fungi: 3" en Bulletin of the Torrey Botanical Club 67 pp. 145 - 146
(1940) "Additions to Florida Fungi: 2" in Bulletin of the Torrey Botanical Club 67 pp. 57 - 58
(1940) " " in Bulletin of the Torrey Botanical Club 67 p. 277
(1941) "More Florida novelties" in Mycologia 33 pp. 441 - 443
(1943) "More new fungi from Florida" in Lloydia 6 pp. 207 - 228
(1944) "More fungi from Florida" in Lloydia 7 pp. 303 - 327
(1945) Autobiography
(1945) "More Florida fungi" in Lloydia 8 pp. 263 - 290
(1945) "New Florida fungi" in Journal of the Florida Academy Sciences 8 pp. 181 - 183
La abreviatura «Murrill» se emplea para indicar a William Alphonso Murrill como autoridad en la descripción y clasificación científica de los vegetales.[3]