NOTES ON CERTAIN CATOSTOMIDS OF THE BONNEVILLE 

 SYSTEM, INCLUDING THE TYPE OF PANTOSTEUS VIRES- 

 CENS COPE. 



By John Otterbein Snyder, 



0/ Stanford University, California. 



For a long time the catostomid described by Cope ^ as Pantos- 

 teus virescens has remained a puzzle to ichthyologists ^. It was 

 originally described as a native of the Arkansas River, where no mem- 

 ber of the genus has since been found. The present paper is intended 

 as a brief contribution toward a settlement of the matter, as the wi'iter 

 has rediscovered the species, abundantly represented in Weber and 

 Bear Rivers, of the Bonneville system of Utah.^ 



The type oi Pantosteus virescens, No. 16758, U. S. National Museum, 

 is a large specimen measuring 370 millimeters in length. The body 

 is long and slender, the caudal peduncle narrow, snout long, mouth 

 large, the broad lips projecting laterally beyond the sides of the head. 

 Along the lateral line the scales grow gradually larger from the head 

 to the tail. On the throat and breast they are very minute. There 

 are 100 scales in the lateral series, 51 between the occiput and dorsal 

 fin, 21 between the lateral line and middle of back, and 15 between 

 lateral line and base of anal. The cranial foramen is open. 



The type specimen has been referred by some authors to Pantos- 

 teus delphinus, a species native to the Colorado basin.* P. delphinus, 

 differs from P. virescens in having a body of somewhat difi'erent 

 proportions as will be seen from an examination of the tables of 

 measurements. The scales of P. delphinus are smaller, there being 

 105 to 112 in the lateral series, 55 to 63 before the dorsal, 20 to 24 

 above the lateral line, and 17 to 20 below the lateral line. 



1 Wheeler's Explor. West of the 100th Merid., vol. 5, 1875 (1876), p. 675. Type No. 16758, Div. Fish, U. S. 

 N. M. ladicating the locality, Cope's expression carries doubt with it; " One species (meaning specimen) 

 accompanying an Amiurus, which is marked Arkansas River, at Pueblo, Mr. C. E. Aiken." 



' Jordan and Evermann, Fishes North Amer., Bull. U. S. Nat. Mus., No. 47, pt. 1, 1896, p. 171, P deU 

 phinus (Cope). 



Snyder, J. O., Proc. U. S. Nat. Mus., vol. 49, 1915, p. 577. 



» Under the authority of the United States Bureau of Fisheries, the writer began an investigation of the 

 fishes of the Bonneville system of Utah, in 1915. After some field work had been done, it was interrupted 

 by the war, and has not been resumed. Specimens referred to were collected at the tune. 



* The writer is indebted to Dr. Max M. ElUs for some particularly fine specimens of P. delphinus which 

 were collected m the Uncompahgre and Rio Florida, tributaries of the Colorado River. 



No. 2508. — Proceedings U. S. National Museum. Vol. 64, Art. 18. 



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