Platysomus gibbosus

Autor/Urheber:

H. ALLEYNE NICHOLSON

Shortlink:

https://dewiki.de/b/3118fa

Quelle:

Wikimedia Commons

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Beschreibung:

Fig. 137.—Platysomus gibbosus, a "heterocercal" Ganoid, from the Middle Permian of Russia. Sharks. Not only are the Ganoids still the predominant group of Fishes, but all the known forms possess the unsymmetrical ("heterocercal") tail which is so characteristic of the Palæozoic Ganoids. Most of the remains of the Permian Fishes have been obtained from the "Marl-slate" of Durham and the corresponding "Kupfer-schiefer" of Germany, on the horizon of the Middle Permian; and the principal genera of the Ganoids are Palœoniscus and Platysomus (fig. 137).

Lizenz:

Public domain

Credit:

http://www.gutenberg.org/files/14279/14279-h/14279-h.htm

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