CYPRINIDA. 57 
tt. Rudimentary dorsal ray attached : 
d. Teeth not molar, in one or two rows : 
e. Maxillary without barbel: 
Jf. Teeth in the principal row 4-4 : 
g. Alimentary canal elongate, about four times length of body ; teeth one- 
rowed, cultriform, with oblique grinding surface and little or 
no hook; premaxillary projectile; lips attenuate, without 
sheath; scales large : 
h. Lateral line almost wanting; mouth oblique; dorsal in front of ven- 
ORAS arse eters ere ait erat nies Nee ace ee so ok noms CoLiscus, 5. 
hh. Lateral line complete; mouth horizontal; dorsal over ventrals: 
—. Teeth elongate with narrow grinding surface and no hook; body 
GO MeN Tee ses Geocacs bp teeeSo a seeheesooe HYBOGNATHUS, 6. 
— —. Teeth short, with rather broad grinding surface and slight hook ; 
body short and rather stout; size small. ....-.-. DIONDA, 7. 
gg. Alimentary canal short, about as long as body; teeth raptatorial, 
usually strongly hooked: 
i. Teeth with grinding surface developed, not crenate : 
j. Dorsal fin beginning above ventrals (i. e., above some ‘part of base 
of ventrals) ; anal basis skort: 
—. Scales small, much longer than deep, with much of the surface ex- 
posed; body stout, compressed; teeth one-rowed, little hooked, 
the uppermost standing out above the surface of the bone; 
size large............----.-.--.-(Subgenus?) ALGANSEA,* 8, 
— —. Scales large, about as long as deep, the usual surface eXposed; 
teeth one- or two-rowed, pretty strongly hooked; size usually 
quibessmiall Se ar cwccmns ees ee (Subgenus ?) HyBopsis, 9. 
— — —. Seales large, much deeper than long on the sides, the ex- 
posed surfaces very narrow ; teeth one or two-rowed, strongly 
hooked ; size moderate or large...-...-....---- Luxius, 10. 
jj. Dorsal fin beginning entirely behind ventrals, between ventrals 
and anal; anal basis elongate. .............. LyrHRuRUSs, 11. 
vi. Teeth with the edges crenate; dorsal fin beginning over middle or 
last rays of ventrals ; scales closely and smoothly imbricated ; 
teeth one-rowed (Moniana) or two-rowed (Cyprinella), 
CYPRINELLA, 12. 
vii. Teeth with edges entire and without grinding surface : 
k. Lips thin, normal; lateral line complete: 
l. Species of small size and weak organization, with the mouth little 
cleft : 
m. Scales comparatively thiek, closely and smoothly imbricated, 
so that the exposed surfaces are higher than long; dorsal fin 
beginning opposite between first and last ray of ventrals, rarely 
slightly posterior; mouth subinferior, somewhat oblique; 
males in spring developing a satin-white pigment in the tips 
of the vertical fins and in the skin of the abdomen; snout 
tuberculate; colors brilliant, pigmented, 
(Subgenus?) PHoToGEnis, 13. 
mm. Scales thin, much exposed; no white satiny pigment (except 
in Codoma?): 
*In A. tincella, the type of Algansea (Leuciscus tincella C. T. V., Hist. Nat. des Poissons 
Xvii, 323), the teeth are said to be 4-4. In some species rateied to Algansea, they are 
5-5. These I refer for the present to Myloleucus, from the type of which genus they 
differ in having but one row of teeth. 
