NO. 1632. PCECILIID FISHES OF LA PLATA BASIN— EIGENM ANN. 429 



lower jaw, about 12 on each side of the upper. Eye a little more 

 than 3 in the head. Origin of dorsal about equidistant from tip of 

 snout to tip of caudal ; origin of anal but little posterior to origin of 

 dorsal; caudal slightly emarginate; anal basis less than half the dorsal 

 basis. Pectorals reaching f to ventrals, about 1^ in head; height of 

 anal 2^ in head. Dorsal, caudal, and anal with conspicuous subtermi- 

 nal black bands, the tips hyaline; middle and base of caudal dusk}-; 

 base of anal hyaline, or with a second dark band; base of dorsal dusky; 

 pectorals and ventrals colorless. 



Fig. 5.— Distal parts of the intromittent organ of Girardinus metallicus. a, third anal 



RAY; 0, FOURTH ANAL RAY, C. FIFTH ANAL RAY. 



2. FITZROYA Gunther.« 



Fitzroya Gunther, Cat. Fishes Brit. Mus., VI, 1866, pp. 299, 307 {multidentatu). 

 Jenynsia Gdnther, Cat. Fishes Brit. Mus., VI, 1866, pp. 300, 331 itineata). 



Type of genus. — Lebias multidentata Jenyns. 



« Fitzroya mvUidentata has several series of tricuspid teeth. Jenynsia lineata is said 

 to have but a single series. Garman considers the species identical, 



