56. LETTCISCUS. 247 



bb. Lateral line complete; pTiarymjcal teeth 3 . 1 — 1 . 3 [?] (Tiaroga). 



•54. Leuciscus cobitis. 



Tiaroga cobitis, Girard, Proc. Ac. Nat. Sc. Philad. 1856, p. 204 ; and 

 U. St. 8f Mex. Bound. Ichthjol. p. 60, pi. 28. figs. 11-14. 



" Head small, subcorneal, depressed. Mouth obliquely terminal, 

 of moderate size, and without barbels of any kind. Upper jaw 

 slightly longer than the lower. Eye of medium size. Isthmus very 

 wide. Body slender, subfusiform, compressed. Fins are well deve- 

 loped ; dorsal and anal narrow and high ; caudal bifurcated. The 

 insertion of the ventrals takes place in advance of the anterior mar- 

 gin of the dorsal. The scales are small ; the lateral line, medial. 

 The phar^Tigeals are similar to those in Oohio. The teeth are like- 

 wise of the same character : slender, subcylindrical upon their base, 

 compressed above, of the raptatorial kind of the hooked type, with- 

 out grinding surface, 1 . 3 — 3 . 1. 



"About two inches and a half in total length, the head forming 

 about the fifth of it. The eyes approximate the upper surface of the 

 head, which is rounded. The upper regions are brownish, with 

 small blackish spots ; the inferior regions are unicolor of a yellowish 

 tint. A black spot upon the base of the caudal fin." 



Rio San Pedro, a tributary of the Rio Gila. 



cc. Lateral line incomplete (Phoxinus, sp.). 

 55. Phoxinus neogseus. 



Chrcsomus eos, Cope, Proc. Ac. Nat. Sc. Philad. 1864, p, 281 (not 



1861, p. 523). 

 Phoxinus neogaeus. Cope, Trans. Am. Phil. Soc. xiii. p. 375. 



D. 8. A. 8. Y. 8. L. lat. 77. 



The height of the body is a little k ss than the length of the head, 

 which is one-fourth of the total (without caudal). Origin of the 

 dorsal fin nearer to the root of the caudal than to the end of the 

 snout. Snout shorter than the diameter of the eye, which is two- 

 sevenths of the length of the head; mouth oblique, reaching to the 

 vertical from the orbit. Lateral line incomplete. Pectoral fins ter- 

 minating at a great distance from the ventral. A blackish band 

 along the lateral line, terminating in a black caudal spot. 



Pharyngeal teeth 5 . 2 — 2 . 4. (Cojie.) 



New Hudson (Michigan). 



b. Pharyngeal teeth in a sinr/le scries (Pseudophoxinus, sp.). 

 56. Leuciscus erythrogaster. 



Luxilus erythrogaster, {Rajin.) Kirthmd, Post. Journ. Nat. Jlist. iv. 



1S44, p. 23, pi. 2. fig. 2. 

 Chrosomus erythrogaster, Cope, Trans. Am. Phil. Soc. xiii. p. 391. 



D. 10. A. 9. V. 8. 

 Scales minute. Upper jaw slightly overlapping the lower ; max- 

 illary extending to below the front mai-giu of the orbit; body thick.. 



