. Carnegie Institution of Washington publication. I <S<; hardly separated from the head. The ulnar process is nearly parallel with the long axis of the hone. The head is farther removed from the axis than in Neptunochelys. In these two respects Atlantochelys resembles Desmatochelys; but it differs from the latter in having a slender shaft. This humerus must have been fully as long as that of Archelon, but it was ot verj different form. A very large turtle is indicated. Family PROTOSTEGIDiE Cope. Marine turtles with the fore limbs converted into flippers resembling thos
. Carnegie Institution of Washington publication. I <S<; hardly separated from the head. The ulnar process is nearly parallel with the long axis of the hone. The head is farther removed from the axis than in Neptunochelys. In these two respects Atlantochelys resembles Desmatochelys; but it differs from the latter in having a slender shaft. This humerus must have been fully as long as that of Archelon, but it was ot verj different form. A very large turtle is indicated. Family PROTOSTEGIDiE Cope. Marine turtles with the fore limbs converted into flippers resembling those ot the Che- loniidae. Carapace greatly reduced, the disk extending not one-half the distance toward the distal ends of the ribs. Peripherals present. Plastron loosely connected with the carapace and with a large median fontanel. Entoplastron T-shaped, with the lateral wings elongated and distally expanded. Epiplastra not certainly known. Xiphiplastra short and bent. Skull large, temporal region broadly rooft over. Region in front of the orbits elongated. Jaws with huge crushing-surfaces. Choanae far forward; not underfloored by the surrounding bones. Genera: Protostega, Archelon, and probably Protosphargis, all of the Upper Cretaceous. The writer is strongly of the opinion that the genera Protostega and Archelon ought to be kept apart from the modern sea-turtles as a distinct family. That both the Protostegidae. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Carnegie Institution of Washington. Washington, Carnegie Institution of Washington
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Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1900, bookyear1908
