conocardium

[Gr. kōnos a cone, and Palcont.: A genus of mollusks, family Cardiade. The shell is trigonal, conical, and gaping. Thirty species are known in this country and Europe. They range from the Upper Silurian to the Carbon iferous period. Britain, if not even as high as the Upper Trias. Pander, and more recently Prof. New berry, consider them the teeth of fishes, the latter gentleman believing them to have belonged to cyclostomatous fishes like our modern lampreys and hag-fishes. Prof. Owen considered them akin to the spines, hooklets, or denticles of naked mollusks and annelids, and other views have been expre ed. ( Nichol son .)