590 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 
we have suggested the new subgeneric name of Rabula. Apparently, 
these species have not enough in common to justify the recognition of 
Rabula as a distinct genus. 
ANALYSIS OF AMERICAN AND EUROPEAN SPECIES OF GYMNOTHORAX. 
a. Dorsal fin beginning over or behind the gill-opening ( Rabula Jordan & Davis). 
b. Dorsal fin inserted far back, nearer vent than gill-opening. Eye moderate, over 
middle of gape ; lower teeth uniserial, with canines in front ; upper 
teeth biserial, the outer teeth small ; vomer with strong canines in 
front, the posterior teeth small, uniserial; posterior nostril nearer 
eye than anterior one. Insertion of dorsal 1 \ lengths of the head 
before vent, much nearer vent than gill-opening. Tail longer than 
rest of body by the length of the jaw. Head 3 in trunk ; gape 2f 
in head; eye 2 in snout. Color much as in Gymnotliorax mordax, 
dark brown with irregular diffuse yellowish spots smaller than eye, 
which run together into irregular marblings ; gill opening small, 
slightly dark; fins nearly plain; belly without dark cross-lines; 
teeth entire «■ Aquje-dulcis, 5. 
bb. Dorsal inserted over or slightly behind gill-opening. 
c. [Teeth in upper jaw uniserial; (dorsal fin in figure beginning a short distance 
behind gill-opening); color yellowish browfi with dark reticula- 
tions, the longitudinal branching streaks studded with oblong yel- 
low spots; spots on belly large, those on throat confluent; dorsal 
and anal yellowish brown with darker clouds; teeth all uniserial]. 
( Kaup . ) Marmoreus, 6. 
c c. Teeth of upper jaw biserial; tail longer than rest of body; color purplish 
brown, nearly plain. 
d. Jaws not capable of being completely closed ; some of the teeth serrate ; outer 
teeth of jaws thickish, bent abruptly backward at tip, the posterior 
margin below distinctly serrate; lower jaw strongly bent upward 
towards the tip, the largest teeth on the bent anterior part of the 
jaws; teeth of the inner row above long, slender, and movable, 
twice as large as the outer teeth ; teeth of inner row of lower jaw 
slender (all lost in specimen examined); vomerine teeth small, 
uniserial, blunt (slender and sharp according to Steindachner) ; 
head small, bluntish, 7-J in body; tail a little longer than rest of 
body ; gape 2& in head ; eye in snout ; dorsal beginning over gill- 
opening ; color dark bluish black, brownish on tail ; pores on jaws N 
whitish Panamensis, 7. 
dd. Jaws with straightish* commissure and hence completely closing; teeth all 
entire. 
e. Tail about half longer than rest of body ; dorsal beginning a little behind 
gill-opening ; vomerine teeth slender and rather long ; teeth in 
two series in each jaw, those of |he inner series largest and mov- 
able ; anterior canines enlarged ; outer teeth of upper jaw bluntish 
and turned backward as in G.panamensis; snout short, bluntish; 
eye large ; head 2f in trunk, 8£ in total ; gape short ; color purplish 
brown, finely mottled with darker, the markings faint. 
Longicauda, 8. 
ee. [Tail but little longer than rest of body; dorsal beginning over gill- 
opening ; vomerine teeth blunt and rounded ; teeth in two series 
in each jaw, those of the inner series longest, movable, and readily 
lost ; anterior canines large ; mouth large, the gape 2 J 7 - to 2i in head ; 
head 8 to in length ; eye small, 3 in snout, inserted over middle 
* Character not verified in G. porphyreas. 
