JULY, 1907. FISHES OF GREAT LAKES, NICARAGUA MEEK. 107 



outer mandibulary barbels reaching to middle of pectoral; dorsal 

 spine strong, its length 2.7 in head; length of dorsal, 1.9 in head, its 

 height 1.7; origin of dorsal to tip of snout 2.7 to 2.9 in length of 

 body; adipose fin long and high, its length 2.3 to 2.6 in body, its 

 greatest height 4.3 to 5 in length of head; distance from last dorsal 

 ray to adipose fin 5.7 to 6.8 in head; length of pectoral fin 1.6 to 1.7 

 in head; pectoral spine robust, its length 2. 2 to 2.3 in head; humeral 

 spine about half length of pectoral spine; ventral 1.8 to 1.9 in head; 

 anal short, its length 2.0 to 2.3 in head; tips of anal rays not 

 reaching end of adipose fin; caudal peduncle strong, its least 

 depth 2.2 in head; caudal fin deeply forked, the lower lobe the 

 longer. 



Color dark olivaceous, more or less mottled with darker, being 

 darkest on middle of sides ; a light band on dorsal fin near its base ; 

 other fins rather dark, all plain. 



San Francisco (8), 150 to 240; Managua (i), 240. 



Family Characinidse. THE CHARACINS. 



This family is represented in the lake by five species, which are 

 easily recognized by their thin cycloid scales, presence of a small 

 posterior adipose fin, and the absence of scales on the head. These 

 species belong to four genera, which are distinguished as follows: 



a. Teeth in upper jaw in two or three series. 



b. Teeth in upper jaw in two series; anal fin with less than 30 



rays; scales 36. Astyanax 107 



bb. Teeth in upper jaw in 3 series; anal rays about 35; scales 

 about 54. Brycon 109 



aa. Teeth in upper jaw in a single series. 



c. Scales large, less than 45 in the transverse series; anal rays 



less than 30. Bramocharax no 



c. Scales small, about 80, in transverse series; anal rays more 



than 40. Rceboides in 



Genus Astyanax Baird & Girard. 



a. Snout long, its length 3.3 to 3.5 in head; maxillary 2 to 2.2 in 



head. nasutus 108 



aa. Snout short, its length 3.7 to 4.2 in head; maxillary 2.3 to 2.6 



in head. * asneus 108 



