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This one, Lepidosteus, has a wide range in America, being found from Florida to Wisconsin. Another American ganoid is Amia calva, the dog-fish or bow-fin, which is very numerous in Western rivers. Both are voracious, but unfit for food.
The Mesozoic Lepidosteidae, again, have, at most, biconcave vertebrae, while the existing Lepidosteus has Salamandroid, opisthocoelous, vertebrae. So, none of the Palaeozoic Sharks have shown themselves to be possessed of ossified vertebrae, while the majority of modern Sharks possess such vertebrae.
The Mesozoic Lepidosteidae, again, have, at most, biconcave vertebrae, while the existing 'Lepidosteus' has Salamandroid, opisthocoelous, vertebrae. So, none of the Paleozoic Sharks have shown themselves to be possessed of ossified vertebrae, while the majority of modern Sharks possess such vertebrae.
At twenty-six years of age, and possessed of so much knowledge, you are only entering upon life, while I am preparing to depart; leaving this world far different from what I hoped it would be in my youth. I will not forget the Bichir and the Lepidosteus. Remember always that your letters give me the greatest pleasure. . .
Lepidotus Mantelli, Agassiz. Wealden. a. Palate and teeth. b. Side view of teeth. c. The fishes of the Wealden are chiefly referable to the Ganoid and Placoid orders. These ganoids were allied to the Lepidosteus, or Gar-pike, of the American rivers. The whole body was covered with large rhomboidal scales, very thick, and having the exposed part coated with enamel.
Among the shells which abound in this cliff are Paludina lenta and various species of Lymnea, Planorbis, Melania, Cyclas, Unio, Potamomya, Dreissena, etc. Wood have found the jaws, teeth, and hard shining scales of the genus Lepidosteus, or bony pike of the American rivers. This same genus of fresh-water ganoids has also been met with in the Hempstead beds in the Isle of Wight.
Again, vast as is the number of undoubtedly Ganoid fossil Fishes, and great as is their range in time, a large mass of evidence has recently been adduced to show that almost all those respecting which we possess sufficient information, are referable to the same sub-ordinal groups as the existing Lepidosteus, Polypterus, and Sturgeon; and that a singular relation obtains between the older and the younger Fishes; the former, the Devonian Ganoids, being almost all members of the same sub-order as Polypterus, while the Mesozoic Ganoids are almost all similarly allied to Lepidosteus.
The Mesozoic Lepidosteidae, again, have, at most, biconcave vertebrae, while the existing 'Lepidosteus' has Salamandroid, opisthocoelous, vertebrae. So, none of the Paleozoic Sharks have shown themselves to be possessed of ossified vertebrae, while the majority of modern Sharks possess such vertebrae.
To his great delight, when the first living specimen of the gar-pike, or modern Lepidosteus, was brought to him, it moved its head to the right and left and upward, as a Saurian does and as no other fish can. The result of this expedition was a valuable collection of fishes and a report upon the fauna and the geology of Lake Superior, comprising the erratic phenomena.
For a closer description of my family of Lepidostei, to which belong all the ante-chalk bony fishes, I am anxious to have for dissection a Polypterus Bichir and a Lepidosteus osseus, or any other species belonging exclusively to the present creation. Hitherto, I have only been able to examine and describe the skeleton and external parts.
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