1906.] NATURAL SCIENCES OF PHILADELPHIA. 327 



head. Rakers short, not numerous and weak. Filaments equal orbit. 

 Isthmus broad and convex. Scales non-striate. Ventral scaly flap 

 f of fin. Pectoral reaching f of space to ventral, and ventral -f- to 

 anal. Vent close in front of anal. Color in alcohol brownish, upper f 

 of body darker and sharply demarcated from lower or whitish surface, 

 and former color extending well below lateral line. Dorsal and caudal 

 brownish, especially middle of each lobe of latter. Pectoral, ventral 

 and anal pale brownish, especially latter. Line of demarcation on 

 sides pronounced by a longitudinal lateral band extending from tip of 

 snout to base of caudal. Iris brownish. Length 6f inches. 



Prof. Garman's view that this is the young of R. argenteo-fuscus Kner 

 is fully established, as I find that the mandible has 8 teeth rather than 

 6 as stated by Cope. 



Leporellus vittatus (Valenciennes). 



Leporinus vittatus Cope, Proe. Amer. Philos. Soc. Phila., XVII, 1877-78 

 (May 17, 1878), p. 690. Peruvian Amazon. Prof. J. Orton. Coll. of 



1877. 



Head 3f ; depth 3|; D. iii, 10, i; A. iii, 8; P. ii, 16; V. ii, 8; scales 

 37? (squamation injured) in lateral line to base of caudal, and 5? 

 more on latter ; 5 scales obliquely back from origin of dorsal to lateral 

 line; 4 scales obliquely up posteriorly from origin of ventral to lateral 

 line; 14? scales (squamation injured) before dorsal; snout 2^ in head; 

 eye 4; interorbital space 2^; least depth of caudal peduncle 3. Gill- 

 rakers short weak fleshy processes. Color in alcohol with back sharply 

 defined from that of band running along lateral line, which is also well 

 defined and dark. A narrow line on flank, well below lateral line, 

 extending from base of pectoral to origin of anal. Top of head with 

 indistinct brownish spots. Dorsal blackish with a broad transverse 

 whitish band below middle. Length 2f inches. 



Castelnau figures Leporinus vittatus Valenciennes, which will be seen 

 to differ at once in the coloration. It shows each scale of the back 

 marked with a single black spot and the dorsal crossed by a blackish 

 transverse band a little above its middle. The side of the head is 

 spotted, and there are also no traces on the trunk of the dark contrasted 

 color-pattern which my example now shows. Kner's figure of Leporinus 

 pidus agrees better, and though it differs according to the figm-e in 

 having a pale dorsal marked above and in front with a dark blotch, 

 another or basal one is mentioned in the description. The figure 

 also shows no trace of the lower dusky line seen on my example, 

 which extends from the pectoral to the anal. Dr. Steindachner 

 records a large example from Cauca which had both dorsal and anal 

 fins marked with blackish bands. 



