ART. XXXIV -A CONTRIBUTION TO THE KNOWLEDGE OF THE 

 ICHTHYOLOGICAL FAUNA OF THE GREEN RIVER SHALES. 



By E. D. Cope. 



The railroad-cut through the bluff ou the west side of Greeu E,iver, 

 Wyoming, at Green River City, has been known for some years for the 

 numerous fishes preserved in the shales through which it is excavated. 

 An investigation into the ichthyology of this horizon and locality was 

 undertaken by the writer, and a report published in the Annual Report 

 of the United States Geological Survey of the Territories for 1870. 

 Eight species of fishes were there described. Subsequently, in my ex- 

 pedition of 1872, 1 discovered a second locality, sixty miles north of the 

 " Fish-cut", near the mouth of Labarge Creek, from which several species 

 of fishes and insects were obtained. A third locality, nearer the main 

 line of the Wasatch Mountains, has been more recently found, and a 

 verj' fine collection of fishes procured and forwarded to me by my 

 friend, H. Schoomaker. The specimens are mostly in a tine state of 

 preservation, and are preserved on slabs of a calcareous shale, with leaves 

 and insects. The mineral is of softer consistence than the slate ot 

 Green River, and thus permits of a more complete exposure of the bony 

 structure of the fishes. In the following pages, sixteen species from this 

 locality are described, all of which are new to science. Many of them 

 are nearly allied to the species already known from the cut at Green 

 Rivei^, belonging to the same genera, but none of them are identical. 

 Three genera not previously represented in the fauna are added. Gen- 

 eral remarks follow the descriptions. 



Dapedoglossus testis. Cope, gen. et sj). nov. 



Char. gen. — Family Osteoglossidcc. A single row of elongate acute 

 teeth on the pren axillary, maxillary, and dentary bones; vomer, tongue, 

 and (?) basihyal bones closely studded with short conic grinding teeth. 

 Mouth rather short. Pectoral fin with the anterior ray elongated; dor- 

 sal fin not elongate, with the anal well separated from the caudal. No 

 beards. 



This interesting genus presents the characters of the family to which 

 I refer it in its segmented scales, posterior dorsal fin, etc., and does not 

 differ widely in essentials from Osteoglossum. The principal differences 



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