NO. 1482. ARGENTINA FISHES— EVERMANN AND KENDALL. 



85 



Color in alcohol: Top of head olive; black bluish gray; side silvery; 

 trace of spot on caudal peduncle and shoulder when scales are removed; 

 dusky punctulations on tip of dorsal and anal rays anteriorly; middle 

 caudal rays dusky. 



23. CYNODON VULPINUS (Agassiz.) 



Rhaphiodon ndpinus Agassiz in Spix, Pise. Brasil., 1829, p. 77, "Habitat in Brasilite 

 fluviis ". 



Cynodon vulpinus Agassiz in Spix, Pise. Brasil., 1829, pi. xxvi. — Castelnau, 

 Anim. Nouv. Exped. I'Amer. Sud, Poiss., 1855, p. 75, pi. xxxix, fig. 1 (Ama- 

 zon; Ucayale). — Perugia, Aim. Mus. Civ. Stor. Nat. Genova, 2d ser., X 

 (XXX), 1890-91, p. 649 (La Plata; Santa Fe; Ascuncion, Paraguay). 



There are 5 specimens in the present collection; definite locality 

 unknown, probably from the market at Buenos Aires. 



Proportional measurements of Cynodon vulpinus. 



Family SILURID.E. 



24. RHAMDIA HILARII (Cuvier and Valenciennes). 



Pimelodus hilarii. CuviER and Valenciennes, Hist. Nat. Poiss., XV, 1840, p. 180, 



Rio San Francisco; Montevideo. 

 Rhamdia hilarii, Lutken, Velhas-Flodens Fiske, 1875, p. 174, and text figure 



(Lagua Santa; Rio San Francisco). — Eigenmann and Eigenmann, Occ. Pap. 



Cal. Ac. Sci., I, 1890, p. 131 (Rio San Francisco and its tributaries; Porto 



Alegri south to Rio Plata). 



Two specimens from Buenos Aires, from which the following notes 

 were taken: 



1. Length without caudal 12.75 inches. Head about 3.57 in length 

 without caudal; greatest width of head 1.5-1: in its length; snout about 

 1.67; eye 9.5 in head, 3 in snout, or 3.33 in interorbital; interorbital 

 2.85 in head; gillrakers 3+10 on each side; fontanelle extending a little 

 beyond eye; occipital process reaching about halfway to dorsal; D. I, 

 7; distance from dorsal to adipose about 10 in length of adipose, 4.5 

 in base of dorsal; A. 10. 



2. Length without caudal 12.5 inches. Head about 3.7 in length 

 without caudal; width of head about 1.58 in its length; interorbital 

 2.84; snout 3.17; eye about 8.3 in head, 2.«il in snout, and about 2.02 

 in interorbital; gillrakers 3+8 on the right side and 3+7 on the left; 



