(^4. OKTIIODON. 27") 



a,b-d. -Half -grown. Coimbra. Presented by Dr. B. du Bocag^e. 

 e-f. Young. Cintra. Presented by Dr. B. du Bocage. 



On a supposed liyhrid between this species and Barhus bocar/ei, see 

 the latter species, p. 92 ; and on another with Leuciscus arcasii, 

 p. 210. 



Chondrostoma viUkonvnii, Steindachncr, 1. c. p. 266, taf. 2, from 

 the Guadiana and GuadalquiWr, is most closely allied to C. pohih'iJis, 

 but distinguished by ha%-ing pharyngeal teeth 6.6 or 7. L. lat. 

 generally 64-66. L. transv. '^• 



7. Chondrostoma phoxinus. 



Heckel, in Russe(i(/ers Reisen, i. p. 1031 ; Sitzffsber. Ak. Whs. Wieii, 

 1852, ix, p. llo, taf. 10; Heckel ^- Kner, S'lissivasserf. p. 225. fios. 

 181,132. 



D. 11. A. 10-11. L. lat. 88-90. L. transr. 17/10. 



Tlie height of the body equals the length of the head, and is 

 nearly two-ninths of the total (without caudal). Snout not much 

 projecting beyond the mouth, the cleft of which is arched. Pharyn- 

 geal teeth 6 . 6. The length of the pectoral tins is four-fifths of that 

 of the head. (If eel:) 



Sign (Dalmatia) ; Livno (Bosnia). 



64. ORTHODON. 



Orthodon, Girard, Proc. Ac. Nat. So. Philad. 1856, p. 182. 

 Scales very small, lateral line present, running along the middle 

 of the side of the tail. Dorsal fin short, without s2>inous ray, com- 

 mencing opposite to the ventrals ; anal tin short. The upper and 

 lower based raijs of the large caudal Jin are unitsualli/ developed. Mouth 

 anterior, crescentic ; intemiaxillaries protractile. Lower jaw ivith a 

 .'<harp anterior edge and a slight knob on the symphysis, and with 

 the labial folds developed laterally only. No barbel. Gill-rakers of 

 moderate length, numerous, compressed, with the inner edge fringed. 

 Pseudobranchite none. The attachment of the gill-membranes to the 

 Lsthmus takes place opposite to the angle of the prteoperculum. 

 Pliarynrjeal bones with the upper limb very broad and concave, st^w- 

 rated by a deep notch from the dentiycrous portion. Pharyngeal teeth 

 strongly compressed, lancet-shaped, 6 or 5 — 6 or 5. Peritoneum 

 black. Intestinal tract with numerous convolutions. 

 California. 



1. Orthodon microlepidotus. 



Gila microlepidota, Ayres, Pruc. Calif. Acad. Kat. Sc. i. 18.jo, p. 21. 

 Orthodon microlepidotus, Girard, U. S. i^- Pac. R. R. U.iped. I'ish. 

 p. 237, pi. 53. tigs. 1-4. 



D. 12. A. 10. V. 10-11. L. lat. 105-110. Vert. 24/20. 

 The height of the body is two-ninths of the total length (without 

 caudal), the length of the head one-fourtli. Snout very broad, of 

 moderate length. Eye rather small, its diameter being one-half of 



t2 



