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Some Typical Upper Eogene Fish Scales from California

David, Lore Rose (1946) Some Typical Upper Eogene Fish Scales from California. In: Fossil Vertebrates from Western North America and Mexico. Carnegie Institution of Washington Publication. No.551. Carnegie Institution of Washington , Washington, DC, pp. 45-79.

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Fossil fish scales belonging to 16 families and to 18 genera from the California Eogene are described in this paper. The majority of the scales come from cores of the Kreyenhagen formation penetrated in oil wells of the San Joaquin Valley. In general, fish scales are plentiful in these strata, whereas there is a sparsity of such remains in the Middle and Lower Eocene. The fossil specimens come from localities rather widely distributed, but not all occurrences of the Kreyenhagen shale have been sampled for scales. The collection shows great uniformity, so far as abundance of the more typical forms is concerned. It is certain that the important and characteristic fish types of Kreyenhagen age are well represented. The assemblage of scales does, however, contain a number of forms that are rare and too fragmentary to warrant description. Unquestionably, still other types will be found in regions not yet explored for this kind of material. Special attention has been paid to scales of Upper Eocene age. Many of these, however, range in occurrence into the Oligocene. The Kreyenhagen formation, for example, which furnished most of the material, includes at its type locality rocks of Oligocene and Upper Eocene age (Jenkins, 1931, pp. 142-143). The present paper is concerned only with the Oligocene and Upper Eocene parts of the wells that were the sources of the fossil material. The age of the fauna is stated to be Upper Eogene rather than Upper Eocene and Oligocene, since the treatment of the Oligocene assemblages is very incomplete, and rocks of this age are represented by only thin sections in the region. A number of new genera and species are established on the basis of scales, since the characters of these structures differ more or less markedly from those of any known form, living or extinct. It must be pointed out that in most instances the fishes to which the scales belong are not known, and the taxonomic position of the genera is frequently doubtful. Diagnoses of the genera have therefore not been given. It seems desirable not to present these diagnoses until such time as the scales and their classification are better known. The genotype species is the only one described for each of the new genera recognized in this paper. Species are described as fully as possible.

Item Type:Book Section
Additional Information:© 1946 Carnegie Institution of Washington. The present study, carried on during 1942 and 1943, is one of several similar investigations conducted at the California Institute of Technology and financed by a number of petroleum companies of California. It is a pleasure to express appreciation to the following individual companies who helped to sponsor these projects: Bankline Oil Company, Continental Oil Company, General Petroleum Company, Richfield Oil Corporation, Shell Oil Company, Standard Oil Company of California, Superior Oil Company, Texas Company, Union Oil Company, Western Gulf Oil Company. The core material from which the specimens of fish scales were collected was furnished by the Superior Oil Company, the Texas Oil Company, the Western Gulf Oil Company, the Richfield Oil Corporation, and the Ohio Oil Company of California. Dr. Chester Stock has given unstintingly of his time and effort in the supervision of many phases of this work. It is a pleasure also to acknowledge the facilities offered by the paleontological laboratory of the California Institute of Technology. Photographs of scales were taken in the laboratories of the Richfield Oil Corporation, Long Beach, California, and thanks are extended to M. L. Natland for his kind assistance.
Funding AgencyGrant Number
Bankline Oil CompanyUNSPECIFIED
Continental Oil CompanyUNSPECIFIED
General Petroleum CompanyUNSPECIFIED
Richfield Oil CorporationUNSPECIFIED
Shell Oil CompanyUNSPECIFIED
Standard Oil Company of CaliforniaUNSPECIFIED
Superior Oil CompanyUNSPECIFIED
Union Oil CompanyUNSPECIFIED
Western Gulf Oil CompanyUNSPECIFIED
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Other Numbering System NameOther Numbering System ID
Balch Graduate School of the Geological Sciences367
Series Name:Carnegie Institution of Washington Publication
Issue or Number:551
Record Number:CaltechAUTHORS:20211022-155425241
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:111601
Deposited By: Tony Diaz
Deposited On:23 Oct 2021 00:00
Last Modified:26 Oct 2021 16:11

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