GEOLOGICAL SUEYEY OF THE TERRITORIES. 469 



ity like types; that from Montana different in coloration. It is a bright 

 green, with numerous blackish speckles on upper surfaces, and brown 

 interscapular spots ; below uniform. 



CnoROPHiLUS TRISERIATUS, Wied ; HelosceteSj Baird. 

 Oarrington's Lake, Yellowstone Basin. 



Spea bombifrons, Cope. . 

 Blackfoot Fork. 



Ban A HALECmA, Bosc. 

 Fort Hall, Idaho. 



Bana peetiosa, B. and G., (United States Exi)loring Expedition; 

 Herpetology, p. 20.) 



Pleasant Yalley, Montana. 



This frog is a near ally of the European E. temporaria^ and is, as 

 Girard remarks, distinguished from the other west-coast species {E. 

 aurora^ B. and G.) by its much shorter limbs. The present species was 

 originally found at Puget's Sound, Washington Territory. 



Eana sbptentrionalis, Baird, (Proc. Acad. Nat. Sci., Phila., 1854, Gl.) 



Abundant; Oarriogton's Lake, Yellowstone Basin, and Fish Creek, 

 Montana. 



PISCES. 



ISOSPONDYLT. 



COREGONUS YILLIAMSONII, Girard ; the Eocky Mountain white fish. 



THYiVLiLLUS TRICOLOR, Copc, (Proc. Acad. Kat. Sci., Phila., 1865, p. 

 80; Gunther, Catalogue Brit. Mus., YI, 201.) 



Specimens from Yellow Creek and the Gallatin Fork of the Missouri in 

 Montana. This species was originally discovered in the Grand liiver, 

 Michigan. It seems to be a rare fish east of the Mississippi; but my 

 friend, J. Dickinson Sergeant, informs me that it has been found abund- 

 antly in a stream in the northern x^art of the peninsula of Michigan. 

 The number of specimens brought by Dr. Hayden from the*head-waters 

 of the Yellowstone indicates that this region is its home. Tbey main- 

 tain well the characters by which it was originally distinguished from 

 the T, vulgaris and T. signifer. The muzzle is shorter and the gape ot 

 the mouth larger than in the former ; the maxillary bone is narrower 

 and longer, reaching to below the middle of the pupil instead of to near 

 the front of the orbit. The length of the head equals the depth of the 

 body and enters the length without caudal fin, 4.5 times. There is some 

 variation in the radial formula as follows: D. 20-22; A. 13-14. Scales, 

 8-9 — 86-90 — 10-12. In the younger si3ecimens the small blue spots 

 tend to form short longitudinal bars. 



Salmo, Linn. 



The species of this genus, found in the streams rising in the Pocky 

 Mountains, are numerous, and, as elsewliere, nearly allied. Those I 

 have observed in Dr. Hayden's collections number three, while a fourth 

 is described by Dr. C. Girard, which I have not met with. The allied 

 species difter as follows. They all belong to the group Salar : 



Depth, 5.75 in length; eye, 4.5 times in head; snout obtuse; 

 caudal fin scarcely emarginate ; Br. IX 8. vlrginaUs, 



