|Marsh Wren (Cistothorus palustris)|
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The wrens are passerine birds in the mainly New World family Troglodytidae. There are approximately 80 species of true wrens in about 20 genera. The wrens are called the winter wen in North America, and in Eurasia it is simply called the wren. Most wrens are about 10 centimetres (4 inches) long, brown (both sexes), and has a short bill that curves slightly down. Its wings are round and it has a short tail.
- "wren (bird) -- Britannica Online Encyclopedia". britannica.com. 2012 [last update]. http://www.britannica.com/EBchecked/topic/649412/wren. Retrieved 27 May 2012.