United States or Moldova ? Vote for the TOP Country of the Week !
The spines, in the genera last mentioned, articulate with the backbone, whereas there are no signs of any such articulation in the ichthyodorulites. Such spines are simply imbedded in the flesh, and attached to strong muscles. "They serve," says Dr. Skeleton of Ichthyosaurus communis, restored by Conybeare and Cuvier. a.
The member of the English "New Red" containing this shell, in those parts of England, is, according to Sir Roderick Murchison and Mr. Strickland, 600 feet thick, and consists chiefly of red marl or slate, with a band of sandstone. Ichthyodorulites, or spines of Hybodus, teeth of fishes, and footprints of reptiles were observed by the same geologists in these strata. Hyperodapedon Gordoni.
Of the first of these, which in the Recent period comprise the shark, the dog-fish, and the ray, no entire skeletons are preserved, but fin-spines, called ichthyodorulites, and teeth occur. On such remains the genera Onchus, Odontacanthus, and Ctenodus, a supposed cestraciont, and some others, have been established. Polypterus. See Agassiz, "Recherces sur les Poissons Fossiles."
Word Of The Day