EXPLORATIONS IN COLORADO AND UTAH. 
33 
Provo Eiver. ; To this species belongs Oila egregiaoi Cope from Beaver River, but the 
specimens called Oila egregia from the Rio Grande, by Cope & Yarrow, must be some 
other fish. The type of Tigoma egregia Girard has 06 scales. L. copei has the scales 
about 80. It is not unlikely that this species is the original of Tigoma gracilis Girard. 
The types of Tigoma gracilis are, however, lost, and the description is too vague to per- 
nnt Identification. The name gracilis is also preoccupied in Leuciscus. The axils in 
the males are deep scarlet in Leucisctis copei. 
9. Leuciscus atrarius (Girard). Chul). M., U.,J. (<Si&o))ia aO'«n« Girard; oftesa Girard; Ti//oma 
squamata Gill; Sqimlius rhomahtis Jordan and Gilbert; Squalius crmreus Jordan and Gilbert ; 
? Hybopsia bivittatus Cope ; ? Hybopsia timjninoyenais Cope.) 
Excessively commou in all waters of the Great Basin except the coldest. It 
reaches a leugth of more than a foot, and is very destructive to the young trout, 
which it captures as they descend the rivers. Reaching a larger size than most of the 
other chubs, it becomes a food lisli of some importance. As the fisli grows older, the 
head becomes proportionately more depressed, and the back more prominent. Such 
large specimens have become the type of Squalius rhomaleus. These large chubs 
swarm in Utah Lake, aud may be taken in the seine, with trout and suckers. Young 
specimens of the same species were named Squalius cruoreus. I have re examined 
tlie types of the latter species and find them to be the young of L. atrarius. The 
two species described as Hybopsis bivittatus aud R. timpanogensis Cope are doubtless 
young chubs, aud probably also of this species. 
Dr. Gilbert has compared the types of Tigoma obesa with those of Squalius cruoreus 
and finds the two identical. The types of obesus are bloated by poor alcohol. The 
name obesus is preoccupied by Leucisctis obesus Storer. 
The species of Leuciscus taken by us during the jireseut summer may be thus 
compared : 
a. Scales very small ; lateral line 80; body rather elongate, the depth about 4 in length ; anal small, 
■with 8 rays ; olivaceous, dark-punctate, sides more or less silvery Copei. 
aa. Scales moderate, 52 to 67. 
b. Anal liu rather small, its rays about 8. 
c. Scales rather small, 60 to 67 ; head rather pointed, the mouth moderate; depth about 4-]- in 
length Pulcher. 
cc. Scales larger, 52 to 58. 
d. Scales before dorsal 23 to 28; back becoming elevated ■with age; dorsal over or rather 
behind ventrals Airariua.* 
bb. Anal fln large, its rays 10 to 13; scales 55 to 58; body more or less compressed. 
e. Anal rays usnally 10 or 11 ; snout rather blunt; jaws equal; eye large, about 3 to 
3^ in head; depth about 4 ; sides with a dusky lateral band : sides aud belly crim- 
son in the male Montanus. 
ee. Anal rays usually 12 or 13; its base 6^ in body ; snout rather sharp ; the lower jaw 
projecting; eye moderate, 4 to 6 in head in adult; depth 3f to 4 in length; sides 
with a plumbeous lateral band, with red above and below it in the males. 
HydropMox. 
* It is not unlikely that Protoporus domninus Cope is based on an immature example of this species. 
The type is from the Snake River at Fort Hall, Idaho. It was 2 inches long, and had the lateral line 
incomplete. 
Bull. U. S, F. 0. 89 3 
