CYPRINIDZ. 59 
xx. Teeth one-rowed, with grinding surface, and the edges crenate- 
serrate; belly sub-carinate; alimentary canal elongate, 
NOTEMIGONUS, 27. 
zzz. Teeth two-rowed, entire, without grinding surface ; alimentary 
CALAN O ELON Mates eect selacmi = are RICHARDSONIUS, 28. 
ss. Both jaws with a hard or cartilaginous brown horny plate, large 
and conspicuous; mouth inferior (Chondrostomatine) : 
—. Teeth 5-4, club-shaped, entire, terminating in a hook, with the 
inner (grinding) surface obliquely cut; anal fin elongate; 
dorsal fin over ventrals; caudal fin with the accessory rudi- 
mentary rays very largely developed; alimentary canal elon- 
gate (?)...--- dese nty Mas eae ee site MIE ACROCHILUS, 29. 
Sff. Teeth usually 6-6, compressed, lanceolate, ereeh , very slightly bent inward, 
one-rowed ; body elongate; jaws even; scales small; fee 
over Sen eeee basal caudal rays largely developed; lower jaw 
sharp-edged, with a knob at the symphysis; no pseudobran- 
chiw; intestinal canal elongate; size large... ORTHODON, 30. 
Sfff. Teeth in the principal row 3-3, without grinding surface; isthmus very 
wide; dorsal behind ventrals......---....----. TriaROGA, 31. 
ee. Maxillary provided with a small barbel: 
y. Premaxillaries not projectile, the skin of the lip and front continuous ; 
teeth in the principal row 4-4, without grinding surface ; 
scales small; dorsal behind ventrals; barbel terminal : 
RHINICHTHYS, 32. 
yy. Premaxillaries projectile, a groove separating the upper lip from the 
forehead : 
z. Teeth without grinding surface : 
a. Teeth in the principal row 4-4; barbels terminal : 
b. Dorsal behind ventrals ; scales small : 
calbateraldinesncompleteee-e—oc=esie aac = anne APOCOPE, 33. 
ce. Lateral line complete-........-.--. (Subgenus?) ERITREMA, 34. 
bb. Dorsal fin over ventrals; lateral line complete.--..-. NocomIs, 35. 
aa. Teeth in the principal row 4-5; barbels lateral : 
d. Dorsal fin over ventrals ; scales large, equal, 
(Subgenus ?) LEucosomus, 36. 
da. Dorsal fin beginning over last rays of ventrals; scales smaller, 
Growided:forwanrd) sf et oeeag sem ace dist eii- SEMOTILUS, 37. 
zz. Teeth with developed grinding surface : 
e. Dorsal fin behind ventrals; scales small...-..--.,...---. AGOSIA, 38. 
_ ee. Dorsal fin directly over ventrals; scales large: . 
J. Head compressed, rounded above....-..-.----- POGONICHTHYS, 39. 
ff. Head broad, much depressed, nearly flat or concave above, resem- 
bling the head of a Cyprinodont..-..- .----.-- PLATYGOBIO, 40. 
dd. Teeth molar, of the grinding type, without grooves or ridges, in three rows, 
the outer deciduous, 2 or 3, 2, 5—4, 2,2 or 3; two or three of 
the teeth blunt and much enlarged; body elongate; head 
tapering: 
—. Angle of mouth with a barbel; upper jaw freely protractile; dorsal over 
VORA Septem ete eine Seay shies. isis msiheisleiaiets MYLOCHILUS, 41. 
——. No barbel; upper jaw not protractile; dorsal beginning behind ven- 
NUE See Saco e aOR OS Erte ree ore Bera aOS MYLOPHARODON, 42, 
ae, Opercular and mandibular bones with external cavernous chambers ; air-bladder 
normal; dentary bones not united; fins without spines 
‘ (Calephoriy: 
