- National Council of Horticulture.
- National Council on Marine Resources and Engineering Development (U.S.)
- National Council on Marine Resources and Engineering Development (U.S.).
- National Dairy Council, Chicago.
- National Data Buoy Center (U.S.)
- National Defense Research Committee (U.S)
- National Ecology Research Center (U.S. Fish and Wildlife Service)
- National Entomological Society (U.S.)
- National Estuarine Inventory (U.S.)
- National farmer and stock grower.
- National Fertilizer Association Plant Food Research Committee. 1925-
- National fertilizer association.
- National Fire Effects Workshop Denver, Colo.) 1978-
- National Fish and Wildlife Foundation (U.S.)
- National Fish and Wildlife Laboratory (U.S.)
- National Fish Habitat Relationships Program (U.S.)
- National Fish Hatchery System (U.S.)
- National Fisheries Institute.
- National Fishery Congress, Tampa, Fla., 1898.
- National Fishery Statistics Program (U.S.)
- National Flower Show Philadelphia, Pa.) 1916-
- National Forage Seed Production Research Center (U.S.)
- National Forest Genetics Laboratory (NFGEL),
- National Forest System (U.S.)
- National Fungus Herbarium.
- National Geographic Society (U.S.)
- National Great Rivers Research and Education Center - NGRREC.
- National Health and Environmental Effects Research Laboratory (U.S.)
- National Health and Environmental Effects Research Laboratory (U.S.). Western Ecology Division.
- National Heart and Lung Institute.
- National Heart Institute (U.S.). Laboratory of Chemistry of Natural Products.
- National Herbarium (South Africa)
- National Herbarium of New South Wales,
- National Herbarium of Victoria.
- National Institute for the Promotion of Science
- National Institute for the Promotion of Science.
- National Institute of Agricultural Botany (Great Britain)
- National Institute of Allergy and Infectious Diseases (U.S.). Office of Recombinant DNA Activities.
- National Institute of General Medical Sciences (U.S.)
- National Institute of General Medical Sciences (U.S.)
- National Institute of General Medical Sciences (U.S.). Office of Recombinant DNA Activities.
- National Institute of Letters, Arts, and Sciences, New York.
- National Institute of Neurological and Communicative Disorders and Stroke. Study of Child Growth and Development and Disease Patterns in Primitive Cultures.
- National Institute of Oceanography of Great Britain.
- National Institute of Science and Technology (Philippines)
- National Institute on Drug Abuse.
- National Institutes of Health (U.S.)
- National Institutes of Health (U.S.). Division of Engineering Services.
- National Institutes of Health (U.S.). Division of Infectious Diseases.
- National Institutes of Health (U.S.). Division of Research Facilities and Resources. Animal Resources Program.
- National Institutes of Health (U.S.). Division of Research Resources. Animal Resources Program.
- National Institutes of Health (U.S.). Office of Recombinant DNA Activities.
- National Institutes of Health (U.S.). Office of the Director.
- National Institution for the Promotion of Science (U.S.)
- National Interagency Fire Center (U.S.)
- National InterAgency Wilderness Conference Tuscon, Arizona). 1993-
- National Iris Gardens (Beaverton, Or.)
- National Irrigation Association (U.S.)
- National Landscape Conservation System (U.S.)
- National Live Stock Producers Association.
- National Microscopical Congress Indianapolis, Ind.) 1878-
- National Mining Association (U.S.)
- National Museum (Australia)
- National Museum (Kenya)
- National Museum (Singapore)
- National Museum of Canada.
- National Museum of Ireland.
- National Museum of Natural History (U.S.)
- National Museum of Natural History (U.S.) Dept. of Invertebrate Zoology
- National Museum of Natural History (U.S.) Pacific Ocean Biological Survey Program
- National Museum of Natural History (U.S.) Palearctic Migratory Bird Survey
- National Museum Of Natural History (U.S.) Dept. Of Botany
- National Museum Of Natural History (U.S.) Palearctic Migratory Bird Survey
- National Museum of Natural History (U.S.). Department of Invertebrate Zoology (Echinoderms)
- National Museum of Natural History (U.S.). Division of Reptiles and Amphibians
- National Museum of Natural Sciences (Canada)
- National Museum of Natural Sciences (Canada). Botany Division.
- National Museum Of Natural Sciences.
- National Museum of Victoria
- National Museum of Victoria.
- National Museums of Canada.
- National Museums of Ceylon.
- National Museums of Kenya
- National Museums of Kenya. Department of Ornithology.
- National Museums of Sri Lanka
- National Norman Horse Association.
- National Nurseries (Lawrence, Kan.)
- National Nurseries,
- National Nursery Co.
- National Nursery Company.
- National Nursery Supply,
- National Nut Growers Association.
- National Nut-growers Association.
- National Ocean Survey.
- National Ocean Survey. Office of Coastal Zone Management.
- National Oceanographic Data Center (U.S.)
- National Oceanographic Data Center (U.S.).
- National Operations Center (U.S.)
- National Operations Center (U.S.). Information and Publishing Services Section.
- National Parks Service
- National Pecan Growers Association. Annual Convention Jacksonville, Florida) 1923-
- National Pecan Growers Association. Annual Convention.
- National pet stock association of America.
- National Petroleum Reserve-Alaska Raptor Disturbance and Mitigation Workshop Fairbanks, Alaska) 1999-
- National Pig Breeders' Association, London.
- National Plant Co.
- National Plant Co., Inc.
- National Plant Company.
- National Plant Materials Center (U.S.)
- National Plant Protection Centre (Bhutan)
- National Planting Service.
- National poultry institute, incorporated, Washington, D.C.
- National Private Non-Industrial Forestry Conference Washington, D.C.) 1979-
- National Recreation Association.
- National Research Council (U.S.)
- National Research Council (U.S.). Botanical Raw Products Committee.
- National Research Council (U.S.). Chemical Biological Coordination Center.
- National Research Council (U.S.). Chemical-Biological Coordination Center.
- National Research Council (U.S.). Committee on Animal Nutrition.
- National Research Council (U.S.). Committee on Celestial Mechanics.
- National Research Council (U.S.). Committee on Neurobiology.
- National Research Council (U.S.). Committee on Nuclear Science.
- National Research Council (U.S.). Committee on Oceanography.
- National Research Council (U.S.). Committee on Pathologic Effects of Atomic Radiation.
- National Research Council (U.S.). Committee on Photobiology.
- National Research Council (U.S.). Committee on Radiation Biology.
- National Research Council (U.S.). Committee on Symposium on Sedimentation.
- National Research Council (U.S.). Committee on the Effects of Radiation on Living Organisms.
- National Research Council (U.S.). Committee on Undersea Warfare.
- National Research Council (U.S.). Committee on Waste Disposal.
- National Research Council (U.S.). Committee on Wild and Free-Roaming Horses and Burros.
- National Research Council (U.S.). Division of Biology and Agriculture.
- National Research Council (U.S.). Division of Medical Sciences.
- National Research Council (U.S.). Division of Physical Sciences.
- National Research Council (U.S.). Highway Research Board. Meeting Washington, D.C.) 1923-
- National Research Council (U.S.). Pacific Science Board.
- National Research Council (U.S.). Patent committee.
- National Research Council (U.S.). Psychology committee.
- National Research Council (U.S.). Research Information Service.
- National Research Council (U.S.). Subcommittee on Radiobiology.
- National Research Council Canada.
- National Research Council Canada. Division of Chemistry.
- National Research Council of Canada.
- National Research Council of Canada. Associate Committee on Animal Nutrition.
- National Research Council of the Philippines.
- National Research Council, Canada. Associate Committee on Animal Nutrition.
- National Riparian Service Team (U.S.)
- National Risk Management Research Laboratory (U.S.). Office of Research and Development.
- National Rose Society.
- National Sand and Gravel Association.
- National Science and Technology Center (U.S.)
- National Science and Technology Center (U.S.). Branch of Publishing Services.
- National Science Board (U.S.)
- National Science Board (U.S.). Committee on Europe in 1992.
- National Science Club, Washington, D.C.
- National Science Foundation (U.S.)
- National Science Foundation (U.S.). Advisory Committee on Ocean Sciences.
- National Science Foundation (U.S.). Center for IPM.
- National Science Foundation (U.S.). Division of Biotic Systems and Resources
- National Science Foundation (U.S.). Division of International Programs.
- National Science Foundation (U.S.). Division of Polar Programs
- National Science Foundation (U.S.). Office for the International Decade of Ocean Exploration.
- National Science Foundation (U.S.). Office of Polar Programs
- National Science Foundation (U.S.). Systematic Biology Program
- National Sedimentation Laboratory (U.S.)
- National Seed and Importing Co.
- National Seed and Importing Company.
- National Shellfisheries Association.
- National Shellfisheries Association. Convention.
- National Show Gardens.
- National Silviculture Workshop Cedar City, Utah) 1991-
- National Silviculture Workshop Mescalero, N.M.) 1995-
- National Single-Comb White Leghorn Club.
- National Spawn and Mushroom Co.
- National Status and Trends Program (U.S.)
- National Steeplechase and Hunt Association.
- National Steeplechase Association.
- National Steering Committee for Management of Seed, Cone, and Regeneration Insects (U.S.)
- National Steering Committee for Management of Seed, Cone, and Regeneration Insects (U.S.). Meeting Boone, N.C.) 1991-
- National Steering Committee for Management of Seed, Cone, and Regeneration Insects (U.S.). Meeting Coeur d'Alene, Ida.) 1995-
- National Steering Committee for Management of Seed, Cone, and Regeneration Insects (U.S.). Meeting Placerville, Calif.) 1993-
- National Steering Committee for Management of Seed, Cone, and Regeneration Insects (U.S.). Meeting Rhinelander, Wis.) 1994-
- National Steering Committee for Management of Western Defoliators.
- National Symposium on Forest Parasites Guadalajara, Mexico) 2003-
- National Toxicology Program (U.S.)
- National Tree Seed Laboratory (U.S.).
- National trotting association.
- National turf bureau, Norwalk, O.
- National Undersea Research Program (U.S.)
- National Union of Conservative and Constitutional Associations.
- National Veterinary Accreditation Program (U.S.)
- National war garden commission.
- National Wetlands Inventory (U.S.)
- National White Wyandotte Club.
- National Wild Horse and Burro Program (U.S.)
- National Wilderness Conference Albuquerque, N.M.) 2014-
- National Wilderness Research Conference Fort Collins, Colo.) 1985-
- National Wildlife Federation.
- National Wildlife Research Center (U.S.)
- National Wood In Transportation Information Center (U.S.)
- National Workshop on Mitigating Losses of Fish and Wildlife Habitats Colorado State University) 1979-
- National Zoological Park (U.S.),
- National Zoological Park Commission (U.S.)
- Nationale Plantentuin Van België
- Nationalmuseum (Sweden)
- Nations, Jonathan
- Native American Holly Farms,
- Native Gardens of Eastern Washington.
- Native Gardens of Spokane, Washington.
- Native Plant Nursery
- Native Plant Society of Oregon.
- Nativel, Naïla
- Natividad, Cheryl A.
- Natividade, Beatriz D.
- Nato Advanced Research Workshop On The Impact Of Solar Ultraviolet Radiation Upon Terrestrial Ecosystems: I. Agricultural Crops Bad Windsheim, Germany) 1983-
- Naton, E
- Natorp, W. A.
- Natradze, Ioseb
- Natsume, Michio
- Natt, Vicki
- Natterer, Johann, 1787-1843
- Natterer, Josef
- Nattero, Julieta
- Nattier, Romain
- Nattrass, A E O
- Nattrass, Nick
- Nattress, William.
- Náttúrugripasafnid, Reykjavik.
- Natur Cymru,
- Natural Areas Conference State University of New York College of Environmental Science and Forestry) 1988-
- Natural Heritage League.
- Natural Heritage Planning and Evaluation.
- Natural History and Science Society of Western Australia
- Natural History Association of Miramichi.
- Natural History Association of New South Wales
- Natural History Club (Louisville, Ky.)
- Natural History Magazine, Inc.
- Natural History Museum (London). Tring Library.
- Natural History Museum (London, England)
- Natural History Museum Of Los Angeles County
- Natural History Museum of Los Angeles County.
- Natural History of the Gila Symposium Silver City, N.M.) 2012-
- Natural History of the Gila Symposium Silver City, N.M.) 2014-
- Natural History of the Gila Symposium Silver City, New Mexico) 2006-
- Natural History of the Gila Symposium Silver City, New Mexico) 2016-
- Natural History Society of Aberdeen.
- Natural History Society of British Columbia.
- Natural History Society of Dublin.
- Natural History Society of Glasgow.
- Natural History Society of Hartford.