This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1897 edition. Excerpt: ... 14 not as large, generally, as those from the Keokuk. The Burlington forms described possess either ten or twelve arms, but Prof. Meek mentioned a specimen with eleven arms which he thought was abnormal. Those from the Keokuk Group possess ten, twelve, thirteen, fourteen, fifteen, sixteen, seventeen ...
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This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1897 edition. Excerpt: ... 14 not as large, generally, as those from the Keokuk. The Burlington forms described possess either ten or twelve arms, but Prof. Meek mentioned a specimen with eleven arms which he thought was abnormal. Those from the Keokuk Group possess ten, twelve, thirteen, fourteen, fifteen, sixteen, seventeen or eighteen arms. The Chouteau forms have a depressed body, the calyx is almost flat and only slightly concave about the column, and the vaults are depressed convex or only moderately elevated. Some of the Burlington forms are constructed upon a somewhat similar plan, but others have a deeply concave calyx and highly convex vault. None of the Keokuk forms are like the Chouteau species, but some of them resemble some of the Burlington species, though generally they are more robust and have deeper calices and higher vaults. The genus Agaricocrinus has not b93n found, so far as we are advised, in the Waverly Group of Ohio, in the Marshall Group of Michigan, in the Kinderhook Group of Indiana. Illinois or Iowa, notwithstanding there are numerous very fossiliferous localities, many of which, like Roekford, Indiana, and Burlington and Le Grand, Iowa, are famous almost all over the world. It occurs in rocks of that age only in the Chouteau limestone of Missouri. The genus has been recognized, however, at almost every locality where the Burlington or Keokuk Group has been determined, in Iowa, Missouri, Illinois, Indiana, Ohio, Kentucky and Tennessee. The abrupt appearance of the genus Agaricocrinus in the Chouteau limestone. in a single locality in Missouri, and its confinement to that geographical locality throughout that geological age. and its distribution over seven states during the two succeeding geological ages, that are represented by the...
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