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''Dakeoceras'' is a simple cyrtoconic ellesmeroceratid genus of cephalopods in the fossil record. All known species come from the Lower Canadian epoch (Gasconadian) of North America. The Dakeoceras shell is an endogastric cyrtocone with the siphuncle on the concave, ventral, side; moderately curved and expanded in the juvenile stages which become reduced in the adult. Forms in which the cross section is broadened, with the venter becoming flattened, are separated as ''Paradakeoceras''. ''Quebecoceras'' is also similar but for its circular cross section and more persistent rate of expansion and curvature. ''Levisoceras'' is more compressed, more strongly curved, and has a higher rate of expansion especially in the vertical plane. ==''references''== * Flower, R.H. 1964. The Nautiloid Order Ellesmerocerida (Cephalopoda); Memoir 12, New Mexico Bureau of Mines and Mineral Resources, Socorro N.M. * W. M. Furnish & Brian F. Glenister, 1964. Nautiloidia --Ellesmerocerida. Treatise on Invertebrate Paleontology, Part K. Geological Society of America, Teichert and Moore (eds). 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「Dakeoceras」の詳細全文を読む スポンサード リンク
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