. Devonian fishes of Iowa. Fishes, Fossil; Paleontology; Paleontology. DEVONIAN FISHES OF IOWA 263 the other, which Dawson figures, displaying the entire outline. This latter exhibits no trace of dorsal ridge scales; impressions of five or six such, however, occur in advance of the dorsal fin in the more poorly preserved specimen. Examination shows that these ridge-scales are distinctly not truncated behind, as Daw- son supposed, but on the contrary are obtusely pointed. Con- sequently the outline sketch given in Fig. 18 d of his Notes and Addenda to the "Geology of Canada" (3d editi
. Devonian fishes of Iowa. Fishes, Fossil; Paleontology; Paleontology. DEVONIAN FISHES OF IOWA 263 the other, which Dawson figures, displaying the entire outline. This latter exhibits no trace of dorsal ridge scales; impressions of five or six such, however, occur in advance of the dorsal fin in the more poorly preserved specimen. Examination shows that these ridge-scales are distinctly not truncated behind, as Daw- son supposed, but on the contrary are obtusely pointed. Con- sequently the outline sketch given in Fig. 18 d of his Notes and Addenda to the "Geology of Canada" (3d edition, 1878, p. 100) requires to be emended in this Fig. 39. Fig. 39. Rkadinichthys modulus Dawson, county, New Brunswick. Cotypes, x 1-1. Lower Carboniferous; Beliveau, Albert The ornamentation of the flank scales as represented in Fig. 18b of the same work is also imperfectly shown. The posterior margin of the scales is indeed strongly serrate, and the exposed surface is covered by from five to six relatively coarse plica-. 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 Eastman, Charles Rochester, 1868-1918; Iowa Geological Survey. Des Moines : Iowa Geological Survey
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