EXPLORATIONS ACROSS THE GREAT BASIN OF UTAH. 



The maxilliuy barbels are slender and scarcely attain to the bases of the pectorals. 

 The nasal barbels extend slight!}' behind the eyes. The infraniaxillary are arranged 

 on a curved line parallel with the jaw; the internal are much more distant from each otlier 

 than tliose of one side; the external are about a tenth of the total length ; the internal 

 about six or seven tenths as long- as the external. 



The band of teeth on the intermaxillaries is extended backward from the angles 

 into a point. 



There are nine branchiostegal rays concealed in a \evy tliiek membrane. Tlie 

 bottom of the sinus of the membrane is very near the mental, the fold being- nearly 

 at the end of the third fourth of the distance between the lower jaw and tlie sinus. 



Tlie dorsal fin commences at tlie 1)eo'innino- of the third tenth of the distance from 

 the snoiit to the end of the caudal fin. Its length equals a tenth of the length, and is 

 little less long- than liigh. The spine is small and simi)le, and its length scarcely equal 

 half that of the fin. 



The adipose fin is low and thin, begins nearly over the sixth or seventh ray of 

 the anal, and appears, in tlie sing-le specimen before us at least, to have separated from 

 the accessory rays by a naked interval. 



The anal fin commences at the end of tlie eleventh twentieth of the distance be- 

 tween the snout and end of caudal fin. Its length is not quite e(]ual to a sixth of 

 the total length ; it rapidl}' increases in height toward the middle, where it somewhat 

 exceeds an eleventh of the extreme length. The last rays rapidly decrease in size. 



The pectoral fins equal in length an eighth of the total; each has a spine, which 

 enters aboiit eleven times in the length, and which is smooth internalh', but on its 

 external border has long serra\ The margin of the fin is round('d. 



The coracoid spine is short, stout, and oblique. 



The A'cntral fins commence behind the end of the fourth tenth (^f the length; each 

 has a length equal to a tenth of the extreme. 



The caudal fin is oblong, gradually and oblitpiely narrowed to the (lul, Avliich 

 appears to have been nearly truncated. 



The supernumerary rays are numerous and well developed, the distance from the 

 anterior to the end of the peduncle being almost as great as the length of the longest 



rays- 



The number and arrangement of the rays is expressed ]}\ the following- fonnula: 



L). I. G. \; A. 4. 11. }; C. 2:J. 7. 12. 11 ; P. I. 10; V. 1. 8. 



The color of the single ill-preserved specimen is an olivaceous-brown, light he- 

 neath, and with the fins not margined by a darker color. 



This species oi Not tans was collected by Dr. Buckley in the i'latte River. It is 

 interesting as being a species of a genus which does not appear to l)e rich in repre- 

 sentatives, and as coming from a moie western locality than any other. 



