. Devonian fishes of Iowa. Fishes, Fossil; Paleontology; Paleontology. 234 IOWA GEOLOGICAL SURVEY In view of the abundance of S. calvini and S. trisulcatus with- in a limited area of the Iowa Upper Devonian, it is indeed surprising that similar dental plates have not been brought to light in other regions of the globe, either from the same, or from earlier or later horizons. With the possible exception of the genera Conchodus and Cheirodus as denned by M'Coy, the latter occurring in the Lower Carboniferous,* it does not appear. Fig. 34. Fig. 34. Dipterus valenciennesi Sedgw. & Murch. Lower
. Devonian fishes of Iowa. Fishes, Fossil; Paleontology; Paleontology. 234 IOWA GEOLOGICAL SURVEY In view of the abundance of S. calvini and S. trisulcatus with- in a limited area of the Iowa Upper Devonian, it is indeed surprising that similar dental plates have not been brought to light in other regions of the globe, either from the same, or from earlier or later horizons. With the possible exception of the genera Conchodus and Cheirodus as denned by M'Coy, the latter occurring in the Lower Carboniferous,* it does not appear. Fig. 34. Fig. 34. Dipterus valenciennesi Sedgw. & Murch. Lower Old Red Sandstone; Orkney. Well preserved headshield showing cranial roofing plates and sensory canals, x 1-1. Original in Yale Museum. *The so-called Conchodus plicatus, described by Dawson from the Coal Meas- ures of Nova Scotia, is regarded by Smith Woodward as having been founded upon an abraded dental plate of 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
Size: 1412px × 1769px
Photo credit: © Paul Fearn / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksub, booksubjectpaleontology
