A NE\Y FOSSIL CYPRINOID, LEUCISCUS TURNERI, FROM 

 THE MIOCENE OF NEVADA. 



By Frederic A. Lucas, 



Curator, Division of Comparative Anatomi/. 



Th(3 name Littehcux firmer i is proposoxl for a small fish oT)taiiir(l by- 

 Mr. II. W. Turner, of the U. S. Geological Survey, fiom the 'i'ertiary 

 of the west side of the valley of the Big Smoky River, Silver Peak 

 Quadrangle, Esmeralda County, Nevada. 



Type. — No. -loOi^a, U.S.N.M., in Catalogue of Fossil Vertebrates. 



In its general aspect this fish bears a strong resemblance to such 

 small cyprinoids as SemotiluH and Leuciscus.^ being of much the same 

 general proportions as Leucisoifi llneatus. The head, as in that 

 species, is a trifle over 3^ in the total length;' depth of head two- 

 thirds of length. There are 19 to 20 precaudal vertebrae and 17 to 

 18 caudals, while Leucucvs llneatuH and Sernotilus atrouiaculatuH have, 

 respectively, 20+17 and 21+18. 



The tail is slightly forked, the lobes slightly rounded. 



The anterior end of dorsal is in line with the anterior end of ven- 

 trals, and the posterior end of dorsal is in line with anterior (^f anal. 

 In Leuclscu.s the dorsal is directly over ventrals and in Semotiltis the 

 dorsal is behind the ventrals. In both LrMclHcna and Semotilus the 

 anterior end of the anal is a little back of posterior edge of dorsal. 

 The fin rays are as follows: Dorsal, 0; anal, 10; pectoral, 11 to 12; 

 ventral, 9; caudal, 23. These may be compared with Leuciscus llneatus 

 and Semotilus atromaculatiis as follows: 



' According to Jordan and Evermann the head is 4| in total length, but this does 

 not accord with the specimen here used for comparison. 



Proceedings U. S. National Museum, Vol. XXIII— No. 1212. 



333 



