NO. 1482. ARGENTINA FISHES— EVERMANN AND KENDALL. 89 



The coloration of both specimens is essentially the same. Back 

 diisk}^ from thick punetiilations; a clu.sky stripe on side of back from 

 nape along base of dorsal to its posterior end; below this a narrow 

 stripe of straw, with dusky punctulations, to base of caudal; again, 

 below this, along lateral line, a sharph^ defined ])lack stripe to base 

 of caudal, continued on the caudal tin as a dusk}' shade; side -below 

 al)ruptly pale, probabl}- white in life; fins all pale; barbels dusk}'; 

 head dusky above and on snout, to a littk^ below eye; abruptly pale 

 below. 



Locality unknown; perhaps from Rio Primero, Cordoba. 



The most pronounced ditferences between P. cordovensis and J\ 

 areolatum are: 



P. coTdovensis has a considerably longer head; first pectoral ray 

 produced; pectoral length without produced ray shorter; distance 

 from tip of snout to origin of dorsal in length without tail is some- 

 what less, 1.66 to 1.69 in head; length of dorsal base very much 

 shorter; dorsal rays fewer; anal rays fewer; and a great difference in 

 coloration. 



Family LORICARIID^E. 



29. PLECOSTOMUS CORDOVA Giinther. 



Plecostomus conlonc Gunther, Ann. Mag. Nat. Hist., II (5th ser.), 1880, p. 11. 

 Cordoba.— EiGENMANN and EigeNxMann, Occ. Pap. Cal. Ac. Sci., 1, 1890, pp. 

 357 and 409 (Bon Jardin on the Rio San Francisco; Port Alegra).— Regan, 

 Monogr. Loricariidte, 1904, p. 212, pi. ix, fig. 3 (Cordoba). 



Gunther had 1 specimen, 9.5 inches long, from Cordoba, as the type 

 of this species. 



We have 7 specimens, 3.7.5 to 13.5 inches long, from Rio Primero, 

 Province of Cordoba, which agree essentially with Giinther's de- 

 scription. 



The principal difference is in the coloration of the fins. According 

 to Gunther, "each ray of the caudal and pectoral is crossed by a 

 number of short black streaks, whilst the dorsal fin is crossed by 6 or 

 7 black zigzag stripes." 



In our examples the fins are all spotted; membranes of all fins 

 excepting caudal with round and elliptical spots in rows on each side of 

 and close to each ray, arranged pinnately in relation to the ray; only 

 the first ray of each of these fins with spots; in the caudal the spots 

 are on the rays only, sometimes extending on the membrane, making 

 short crossbars. If the dorsal is not fully expanded the spots have 

 somewhat the appearance of zigzag stripes; in the smallest '2 examples 

 the spots of all the fins coalesce to some extent, and in the dorsal, 

 especially in the smallest specimens, are actually cross stripes. 



In the smallest specimen the spinules on the posterior edge of the 

 lateral plates are proportionally larger than in the larger examples. 



