PLECTOSPONDYLI OYPR1N1DAE GILA TAENIA. 659 



anal radii, the elegant coloration, and other 'characters. Body of average 

 proportions, its depth entering the length without caudal fin four and one- 

 third times, and exactly equal to the length of the head. The head is com- 

 pressed and the lips equal ; the mouth is obliqiie, the end of the maxillary 

 attaining the anterior line of the orbit. The orbit is large, entering the 

 head three times and a fifth, and equaling the width of the convex inter- 



12 



orbital space. Scales, Hs ; 33 in front of dorsal fin. Lateral line complete, 



deflexed between pectoral and ventral fins. Radial formula : D. I. 9 ; A. I. 

 10; V. 9; P. 11 ; reaching ventrals, which reach vent. Dorsal first ray 

 equidistant between the basis of the caudal and the anterior nostril. 



Total length, O m .073 ; length to anal fin, O m .042 ; to ventral, O m .031 ; 

 length of head, O m .014 ; length to orbit, O m .0036 ; width to posterior nostrils, 

 CT.004 ; width at middle of pterotic, O m .0062. The sides are pure silvery to 

 the lateral line of pores, above which a blackish vitta extends from the end 

 of the muzzle to the caudal fin. Above this is a narrow very white line, 

 which extends to the base of the caudal fin, and above this the entire dorsal 

 region is blackish. Fins unspotted. 



Numerous specimens from Provo near the lake (No. 667,667 S., and 666). 

 Collected by Dr. H. 0. Yarrow and H. W. Henjhaw. 



This little fish is called by the Mormon settlers Silver-side or Leather- 

 side Minnow, and is very common in Provo River. Is from three to five inches 

 in length ; male of an iridescent green color, blackish back. Silvery stripe 

 commencing just above middle third of body ; just below a bright orange 

 yellow stripe, and under this a fine black stripe. Belly white ; iris black ; 

 female without the bright lines, and much lai'ger. This beautiful little fish 

 is very abundant in the rocky holes of the Provo River, and is the favorite 

 food of the trout, inhabiting the same locality. They are found on the 

 whole course of the river, from just below the fall, in Provo Canon, to the 

 mouth, but strange to say are seldom seen in Lake Utah, into Avhich this 

 river empties. 



We are inclined to believe that the trout Salmo virginalis, as men- 

 tioned previously, visit the mouth of the river not only to get into cooler 

 water, but to feed upon these minnows. Their spawning time is early in 



