TRAP - 4 reference results
trap-door spider, spider of the same family as the native American tarantula. Trap-door spiders dig burrows, which they line with silk and protect by constructing one or two circular, hinged trap doors. The spiders emerge through the snug-fitting camouflaged doors to search for prey. Usually the burrow entrance has a door, the outer surface of which is camouflaged to blend in with the surrounding terrain. If a second door is present, it is usually below the entrance door. Trap-door spiders are classified in the phylum Arthropoda, class Arachnida, order Araneae, family Ctenizidae.
The Columbia Electronic Encyclopedia Copyright © 2004.
Licensed from Columbia University Press
Licensed from Columbia University Press
Wolf Trap Farm Park for the Performing Arts: see National Parks and Monuments (table).
The Columbia Electronic Encyclopedia Copyright © 2004.
Licensed from Columbia University Press
Licensed from Columbia University Press
Subsurface reservoir of petroleum. The oil is always accompanied by water and often by natural gas; all are confined in porous rock. The natural gas, being lightest, occupies the top of the trap and is underlain by the oil and then the water. A layer of impervious rock, called the roof rock, prevents the escape of the petroleum. The part of the trap that is actually occupied by the oil and gas is called the petroleum reservoir.
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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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