195 



The first of the fossil-fishes of the Green River shales was discovered by 

 the late Dr. John Evans as early as 185G, and was submitted to the examina- 

 tion of the writer. Several specimens, both of the bufi'-colored and dark 

 bituminous shales, containing fossil-fishes, have been presented to me by 

 Judge W. A. Carter and Dr. J. Van A. Carter, of Fort Bridger, Wyoming. 



Professor Cope describes seven species, including one of those described 

 by me, from the Green River shales. Two are named Clupea himulis and 

 C. pusilla, and a third Osteoglossum encaustum. The others are referred to 

 two extinct genera with the names of Asineops squamifrons and A. viridensis, 

 Erismatopterus Rickseckeri and E. levatus. 



CLUPEA. 



Clupea humilis. 



The species was originally described in the Proceedings of the Academy 

 of Natural Sciences of Philadelphia for 1856, page 256. It was indicated 

 from a specimen consisting of an impression of a nearly complete fish in a 

 l)iece of shale, which looks like one-half of a rounded, water-worn fragnuMit. 

 The fossil was found by Dr. Evans on Green River, and was stated by him 

 to have been derived from the Tertiary rocks of that locality. The fish is 

 represented in Fig. 1, Plate XVII, of the natural size. It has the ordinary 

 form of living species of herring, and presents the characters of the genus. 



This small herring in its total length has measured about 3^ inches. The 

 back is slightly arched, and the dorsal fin is situated just in advance of the 

 middle. The ventral border is strongly arched, and is rather abruptly nar- 

 rowed from the anus. The ventral fins are placed beneath ihc back of the 

 middle of the dorsal fin. The head is pointed. The tail is deeply forked, 

 and its pedicle is rather narrow. 



The number of vertebras appears to be about thirty-four, of which at least 

 twenty are dorsal, tlie remainder caudal. The notochord appears to liave 

 extended continuously through the perfoi'ated vertebral bodies. 



The depth of the l)ody at the fore part of the dorsal fin is four and a luilf 

 times less than the length. The length of the head slightly exceeds the 

 depth of the body. The eyes are large. 



The pectoral fins are destroyed, but their connection with tli(^ body was 

 just below the position of the operculum. Tlie ventral liiis ('(nilaiii seven 

 rays. 



