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By T. w. STANTON. scales have been obtained from the Mowry shale, from the Aspen shale, and from other peds of about the same age in the areas where Fish remains are extremely abundant in these shales are not characteristically develseveral Cretaceous formations of the Rocky oped, but no attempt has been made to do Mountains and Great Plains, but except in thorough collecting even in these formations, the Niobrara formation of Kansas, a fish because no one in the Survey was qualified to skeleton well enough preserved for descrip-1de:o.tify _ ,the scales. Tpe _ scales from other tion or identification is the greatest rarity. formatioils in the same region have been The fishes are represented by separate scales, obtained incidentally in collecting invertebrate in some places associated with a few vertebrae fossils and are so few in number that they and other fragmentary bones or by isolated probably do not fairly represent the fish. teeth. In the original descriptions of both faunas of the seas in which ,the formations the Mowry and the Aspeh shales of Wyoming were deposite<. l. Similarly, the four species the presence of fish scales is mentioned as a based on scales from the Chico group were all characteristic feature. Fossils of other classes obtained in the Moreno formation at two. are usually very rare in beds containing many neighboring localities on the west side of San fish scales. Many of the scales ' are beautifully Joaquip. Valley, Cal., and can only be regarded preserved and show varied forms and more or as suggest ive of the relationship, or lack of less complex sculpture. • relationship, between the Cretaceous fish faunas It had long been regretted that these fish of the Pacific coast and those of the Rocky scales had not been studied systematically, Mountain region. The enormously thick secand when several papers on the scales of tion referred to the Chico group in this part of living and fossil fishes •were published by Prof. California has been divided by Anderson and Theodore D. A. Cockerell/ of the University of Pack 2 into t he Panoche formation below and Colorado, Boulder, Colo., the hope was again the Moreno formation at the top. The Paquickened that these Cretaceous fish scales noche formation is said to have a maximum might prove to be of some value in strati-' thickness of 21 000 feet and the Moreno formagraphic identifications and correlation. Prof. tion 2,500 or 3,000 feet. Fish scales are known Cockerell's offer to study fish. scales collected to be present 'in the Cretaceous formations of by the United States Geological. Survey was the Coastal Plain, extending from New • Jersey therefore welcomed, and early In 1916 the to Texas, but no attempt has yet been made material from the Western States was placed to assemble them for study. The collections in his hands. As a result of its study the ac-here treated are all of Upper Cretaceous agecompanying ;papei: has been pre~ared.. . that is, they are younger than the Comanche In connectiOn with the Surveys stratigraphiC and Shasta series. and a...

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