48 
Indiana University Studies 
a few chromatophores irregularly scattered on the scales 
above the silvery band ; a few chromatophores collected at the 
base of the caudal in an indistinct spot. 
Subfamily stethaprionin^e. 
Ephippicharax orbicularis (C. & V.). 
17306, 1, 30 mm., Cachuela Esperanza. Mar., 1922. 
Subfamily serrasalmonin^e. 
Serrasalmo marginatus (Valenciennes). 
17120, 1, 160 mm., Lake Rogoagua. Oct., 1921. 
Serrasalmo spilopleura Kner. 
17116, 4, 145-175 mm., Lagoons near Reyes. Oct., 1921. 
17117, 1, 105 mm., Huachi. Aug., 1921. 
17118, 3, 152-200 mm., Ivon. Feb., 1922. 
17119, 1, 195 mm., Lake Rogoagua. Oct., 1921. 
Serrasalmo humeralis C. & V. 
17121, 3, 190-205 mm., Ivon. Feb., 1922. 
Subfamily myliile. 
Catoprion men to (Cuvier) . 
17113, 1, 75 mm., Lagoons near Reyes. Oct., 1921. 
Metynnis roosevelti Eigenmann. 
17115, 11, 96-155 mm., Lagoon near Reyes. Oct., 1921. 
17341, 3, 24-26 mm., Ivon. Feb., 1922. These immature specimens prob- 
ably belong here. 
Mylossoma aureus (Spix). 
17114, 10, 32-70 mm., Cachuela Esperanza. Mar., 1922. 
Mylossoma albiscopus (Cope) . 
17309, 1, 200 mm., Rurrenabaque. Oct., 1921. 
Subfamily CHARAClhLE. 
Charax gibbosus (Linnaeus) . 
17125, 4, 78-130 mm., Reyes. Nov., 1921. 
17308, 1, 47 mm., Lake Rogoagua. Oct., 1921. 
