[0o. 
II. 
FISHES OF THE ROCKY MOUNTAIN REGION 165 
The western forms are all or mainly var. sucklii, which approaches C. ardens. 
(Common Sucker.) 
Upper lip broader, 4 to 6 rows of papilla; species of Great Basin (Heart Lake, Yellow- 
Stone baTk)) tt . .  Catostomus ardens (Jordan and Gilbert). 
Species of the Rio Grande ee Gedo to Chihuahua; scales 80 
Pantosteus plebeius (Baird and Girard). 
Species of Wyoming, Montana and Northern Colorado, scales goor more 8. 
Head comparatively large, 4 in length of body; scales 16-go to 110-14; upper lip 
‘with 5 to 8 series of tubercles; lower lip incised to base; dorsal fin with usually 11 
rays (Boulder Creek, abundant; Platte River; Montana). 
Catostomus griseus (Girard). 
(Var. lactarius (Girard) appears to have larger scales, 88 to 90; var. retropinnis 
(Jordan) has fuller lips and a more backward dorsal. (Both these supposed varieties 
are from Milk River, Montana.) 
PeResariere lente eer eet Pel sary weap Sent oy Peek) ay, SM wy eps ae) ede Oe 
Species of Colorado River Basin. . Pere ROM Iiped e/a seo ATO! 
Species of Missouri and Columbia R. Basis Mae eh, colton snipes 
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Pana ents! nels oetaneners 
Fic. 2.—Campostoma anomalum. 
Size up to 2 feet; sides and fins largely orange; dorsal rays 11 to 13; scales 17-98 to 
TO$ SUF hi) shi . . . .  Catostomus latipinnis (Baird and Girard). 
(Henshall gives C. Pe shohe Cope, from Montana and Wyoming, as distinct.) 
Size up to one foot; dorsal rays 10; scales 16-96 to 105-14 (W. Colorado; Wyom- 
Mg) Ait . . . .  Pantosteus delphinus (Cope). 
(P. virescens Gone ene in error aid anette, Colo., is the same.) 
Length to 2} feet; head quite long and slender; scales 95 to 114 in lateral line 
(Montana). . . . .  . Catostomus catostomus (Forst.) (Long-nosed sucker). 
Length to about one foot; head short, conic; scales go to roo in lateral line (Montana) 
Pantosteus jordani (Evermann). 
Another genus of suckers, Chamistes, is confined to the Great Basin, with species in 
Utah, Nevada and Oregon. It has the mouth very large, and terminal instead of 
inferior as it is in Catostomus, and other characters. 
