Definition: The bathypelagic zone biome comprises the marine water column below approximately 1000 m water depth - the maximum depth to which detectable daylight penetrates in all but the clearest oligotrophic waters - and extends to about 2500 - 2700 m water depth. In the temperate Atlantic, the beginning of the bathypelagic zone biome approximates to the deep oxygen minimum and the base of the permanent thermocline.
Definition: National Museum of Natural History, Smithsonian Institution (USNM), Washington, District of Columbia, USA.\r\nNMNH and USNM both refer to the National Museum of Natural History. Collections are associated with one or the other acronym. US, the US National Herbarium, is a collection within the National Museum of Natural History. URL for main institutional website, http://www.mnh.si.edu/rc/\r\nURL for institutional specimen catalog, http://collections.mnh.si.edu/