NEW YORK ( CNN ) -- Bidding failed to meet expectations Saturday on a uniquely complete skeleton of a Jurassic-era dryosaurus -- a long-necked , plant-eating dinosaur -- so it was no-sale for the centerpiece at an auction of rare skeletons , fossils and other prehistoric memorabilia . Fossils including dinosaur skeletons are on display at the I.M . Chait Gallery on Saturday . Auctioneers at the I.M . Chait Gallery had hoped the 150-million-year-old , 9-foot-long dryosaurus would sell for as much as $ 500,000 , but the bidding did not add up . Two museums are said to still be interested in acquiring the skeleton , being sold by Western Paleontological Laboratories out of Utah . An 18,000-year-old , 7-foot-tall and 15-foot-long skeleton of a teenage woolly mammoth from Siberia took the auction 's top price , fetching close to $ 60,000 . A completely opalized green , blue , yellow and red ammonite fossil measuring 2½ feet in diameter went for close to $ 50,000 . Both were bought by private collections . `` The woolly is so special because it was n't fully grown and can therefore fit in someone 's living room , '' says Josh Chait , director of operations at the gallery . `` A collector 's dream . '' Watch collectors stroll among fossils » . The ammonite , an extinct marine animal , turned to opal as part of the fossilizing process . Ammonite fossils have been found in ancient seabeds in Alberta , Canada .
Auctioneers had hoped remains of dryosaurus would fetch half a million dollars . Bids did n't measure up , so 9-foot skeleton from Jurassic Period remains unsold . Fossil of a teenage woolly mammoth sold for close to $ 60,000 at auction . Huge opalized fossil of an extinct sea creature went for almost $ 50,000 .