(German, ‘wonder chamber’)
By the end of the 16th century the term was virtually synonymous with Kunstkammer. However, it was originally used in mid-century to describe a room containing a private collection of rare natural history specimens such as corals, but above all curiosities such as mandrakes, misshapen antlers, or narwhal tusks. Wunderkammern were predecessors of natural history museums.
http://www.metmuseum.org/toah/hd/kuns/hd_kuns.htm Description and illustrations on Metropolitan Museum of Art website.