NO. 1532. PmclLIID FISHES OF LA PLATA BASIN— ElOENMANN. 



427 



ff. Claspers consisting of antler-like processes at tip of second prolonged 

 ray of the anal. Alimentary canal more than twice the entire length. 



PhaUoceros, 5. 

 aaaa. Each jaw with bands of conical teeth; anal of male not modified. 



;/. Origin of dorsal in advance of anal. Anal 10-lH; D. 9-18. Depressed 



forward. An air bladder Fnndulus, 6. 



gg. Origin of dorsal behind that of anal. 



h. A. 8-15; D. 6-11; lat. 1. 29-44. Body subcylindrical. No air 



l)ladder Rivuhis, 7. 



hh. Anal 20-29; D. 17-2:5; lat. 1. 30-48. Head and body compressed. 



Cijno/ebias, 8. 



Fig. 2.— Tip of intromittent organ of 

 acanthophacelus r et i cu l at u s. a, 

 third anal ray, b, fourth anal ray; 

 c, fifth anal ray. 



Fig. 3. — Tip of intromittent organ of 

 Glaridichthys uninotatus. a, third 



ANAL RAY. 6, FOURTH ANAL RAY; C, 

 FIFTH ANAL RAY. 



1. ILYODON" Kigenmann, new genus. 



Intestine about 3 times as long- as the bod}' ; dorsal and anal poste- 

 rior. D. 16-lS; A. 14 or 15; teeth bicuspid, in a single series; scales 

 small. 



(I iXv<;, ooze; odovs, tooth. 



