Title: Elements of geology : a text-book for colleges and for the general reader
Identifier: elementsofgeolog00leco (find matches)
Year: 1892 (1890s)
Authors: LeConte, Joseph, 1823-1901
Subjects: Geology
Publisher: New York : D. Appleton and Co.
Contributing Library: Smithsonian Libraries
Digitizing Sponsor: Biodiversity Heritage Library

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FAUNA OF THE CARBONIFEROUS AGE.
Text Appearing After Image:
\, : Fig. 576. Fig. 575. Figs. 571-576.—Carboniferous Fishes—Placoids• 571. Cochliodus contortus. 572. Petalodus destructor (after Newberry). 573. Cladodus spinosus (after Newberry). 574. Orodus mammi- lare (after Newberry).—Ganoids; 575. Amblypterus macropterus. 576. Tooth of Holoptychius Hibberti, natural size. still the rulers of the seas. Of Placoids, one has been found with dorsal spine eighteen inches long, another with spine three inches broad and nine and a half inches long, although much of the point is broken off. Their teeth, too, are beginning to assume more of the character of true shark's-teeth. They are no longer wholly Cestracionts (Fig. 571), but also now Tlybodonts, having teeth somewhat like modern sharks, but rounded on the edges (Figs. 573 and 574). Among Ganoids, the well-protected but sluggishly-moving Placoderms have passed away, but the Sauroids continue in increased numbers and size. Bony, en- ameled scales of the Megalichthys and Holoptychius are found, two to three inches across; and jaws of the Holoptychius, a foot or more long, armed with Saurian teeth, two inches in length (Fig. 576). Also,

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