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|synonyms = ''Canadia sparsa'' }} ''Hallucigenia'' is a genus of Cambrian animals known from articulated fossils in Burgess Shale-type deposits in Canada and China, and from isolated spines around the world. Its quirky name reflects its unusual appearance and eccentric history of study; when it was erected as a genus, the animal was reconstructed upside down and back to front. ''Hallucigenia'' is now recognized as a "lobopodian worm". It is considered by some to represent an early ancestor of the living velvet worms, although other researchers favour a relationship closer to arthropods.〔 ==Description== ''Hallucigenia'' is a 0.5—3.5 cm long tubular organism with seven or eight pairs of slender legs, each terminating with a pair of claws. Above each leg is a rigid conical spine. The 'head' and 'tail' end of the organism are difficult to identify; one end extends some distance beyond the legs and often droops down as if to reach the floor. Although some specimens display traces of a gut, the internal anatomy has not been formally described. Recent research suggests that the extended element is an elongated head with two simple eyes, a mouth with radial teeth, and pharyngeal teeth within the front of the gut.〔Morelle, Rebecca, (Face of bizarre sea creature Hallucigenia revealed ), BBCNews, Science and Environment, 2015.06.25〕 ''Hallucigenias spines are made up of one to four nested elements. Their surface is covered in an ornament of minute triangular 'scales'. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hallucigenia」の詳細全文を読む スポンサード リンク
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