1856.] 209 



pharyngeal bones are long and slender, slightly expanded upon their convexity, 

 with the inferior limb much more slender than the upper. The teeth are of the 

 raptatorial Icind, of the hoolied type without grinding surface, subconical, 

 slightly hooked, and disposed upon a double series of two and four or five, 

 thus: 2 I 4 4 | 2, or 2 [ 55 | 2. 



1. Ptychocheilus grandis. Gila ffrandis, Ayvles, Vroc. Cal. Acad. Nat. Sc' 

 i. 1854, 18. Piychocheilus major^ Agass. Amer. Journ. of Sc. 2d. Ser. xix. 

 1855, 229. 



San Francisco, Cal. Dr. Newberry. 



2. Ptychocheilus oregonensis. Cyprinus {Leuciscus) oregonensis, Rich. Faun. 

 Bor. Amer. iii. 1836, 305. Ptychocheilus gracilis, Agass. &. Pick. Amer. Journ. 

 of Sc. 2d. ser. xix. 1855, 229. 



Specimens of this species were collected at Fort Vancouver and Fort Steila- 

 coom, by Dr. Geo. Suckley, at Astoria, 0. T. by Lt. Trowbridge, and in Villa- 

 mette River, by Dr. Newberry, under Lt. Williamson, U. S. A. 



3. Ptychocheilus rap ax. This is a large species too, differing from P. grandis 

 by a proportionally shorter head, a more advanced position of the ventral fins 

 and by much smaller scales on the dorsal region in advance of the dorsal. The 

 inferior limb of the pharyngeal bones is not so long and slender, and there are 

 but four teeth upon the main row, instead of five. The teeth and bones are 

 stouter. Colors, blackish brown above ; whitish beneath. 



From Monterey, Cal. ; collected by Lt. W. P. Trowbridge, TJ. S. A. 



4. Ptychocheilus lucius. A very characteristic species. The body is com- 

 pressed, but the head is flattened or depressed and very much developed, con- 

 stituting nearly the fourth of the entire length. The dorsal and ventrals are 

 situated quite posteriorly. The scales are below the medium size, and the 

 lateral line is bent downwards upon the abdomen. The pharyngeal bones are 

 very slender ; the inferior limb is almost exiguous and proportionally as long 

 as in P. grandis. There are, however, but four teeth upon the main row, instead of 

 five, as in the case of P. grandis. Color bluish grey above ; silvery gclden 

 beneath. 



Collected in the Rio Colorado, by A. Schott, under Major W. H. Emory, 

 Commissioner U. S. and Mex. Boundary. 



5. Ptychocheilus vorax. The head is also depressed in this species, but it is 

 much smaller since it contitutes the two-ninths of the entire length. The 

 body is much deeper than in P. lucius, and the ventrals are situated more in 

 advance of the dorsal. The dorsal itself is not situated so far back. The scales are 

 very small upon the dorsal region between the dorsal fin and the occiput. 

 Bluish above ; silvery beneath. 



Specimens were brought home by Lt. E. G. Beckwith, U. S. A. The precise 

 locality, not known. 



APPENDIX, 



The following species are here recorded as complementary to the preceding 

 ones. 



1. Hybognathus REGIUS. A large and beautiful species, the largest that 

 has, so far, come to our knowledge, some of the specimens measuring seven 

 inches in length. The body is gracefully elongated, compressed, fusiform 

 in its outline. The greatest depth, taken immediately in advance of the dorsal 

 fin is contained about five times in the length, or five, and a third of a time. 

 The head is of moderate development, subconical, subtruncated, contained six 

 times in the total length. The mouth is quite small. The isthmus, very narrow. 

 The origin of the ventrals recedes a little from the anterior margin of the dorsal, 



16 



