FISHES 55 



3. Cycleptus Rafinesque. Body elongate and similar to the two 

 previous genera, but with a closed fontanelle; head very small: i 

 species. 



C. elongatus (LeSueur). Blackhorse; Missouri sucker. Length 

 750 mm.; head 6 to 8; depth 4 to 5; color blackish; dorsal fin with 30 

 rays, the anterior 2 or 3 being much prolonged; anal fin with 7 to 8 

 rays; scales 9-56-8; mouth small; upper lip thick and pendant: 

 Mississippi Valley, often common in large streams; a good food fish. 



4. Pantosteus Cope. Mountain suckers. Body small, elongate, 

 similar to Catostomus; mouth ventral, with a cartilaginous sheath on 

 each jaw: several species, in the Rocky Mountain region, all of little 

 food value. 



P. generosus (Girard). Length 200 mm.; head 5; depth 5.5; color 

 light brown, with dusky spots; chin, fins and lateral band red in male; 

 rays of dorsal fin 9; scales 15-81-14: Great Basin of Utah; very 

 common. 



P. plebeius (Baird & Girard). Length 300 mm.; head 4.6; depth 

 4.75; color dark brown with orange lateral markings in male; scales 

 80; body stout: basin of the Rio Grande; very common. 



P. delphinus (Cope). Length 300 mm.; head 4.75; color bluish 

 above, yellowish below; sides of male rosy; rays of dorsal fin 10; scales 

 16-96 to 105-14; tail very slender: basin of the Colorado; very common. 



P.jordani Evermann. Length 300 mm.; head and depth 5; color 

 dark greenish, speckled; males with orange lateral band; dorsal fin 

 with 10 or II rays; anal with 7 rays; scales 16-90 to 100-14, 4^ before 

 the dorsal: basin of the upper Missouri and Columbia; generally 

 distributed. 



5. Catostomus LeSueur. Fine-scaled suckers. Body elongate; 

 mouth rather large, ventral; upper lip thick, papillose and protractile; 

 lower lip very large with a broad free margin usually in two more or less 

 distinct lobes; scales small; dorsal and anal fins high and rather short: 

 many species, all North American except C. rostratus Tilesius, which 

 occurs in Siberia. 



Key to the Species of Catostomus here described 

 ai More than 80 scales in the lateral line. 



bi Upper lip broad, with 5 or 6 rows of papillae. 



Ci Upper lip not projecting; in the Colorado River basin. 



dx In the lower Colorado basin C. latipinnis. 



di In the upper Colorado basin C. discobolus. 



C2 Upper lip very long and pendant; in the upper Missouri. . C. griseus. 



C3 In northern California C. rimiculus. 



bo Upper lip narrow, with about 3 rows of papillae. 



