326 PROCEEDINGS OF THE ACADEMY OF [June, 



Subgenus RHYTIODUS Kner. 



Scales small, 80 to 90 or more in a lateral series, 

 Rhytiodus microlepis Kner. 



Head 4f ; depth 5f ; D. ii, 10, i; A. ii, 8, i; scales 77 in a lateral series 

 to base of caudal, and 8 more on latter; 12 scales obliquely back from 

 origin of dorsal to lateral line; 9 scales obliquely up posteriorly from 

 origin of ventral to lateral line; 8 scales from origin of ventral in a 

 similar way; about 23? (squamation damaged) scales before dorsal; 

 snout 2f in head; eye 5; interorbital space 2; pectoral H; ventral 1^; 

 least depth of caudal peduncle 2f. Small short slender weak gill- 

 rakers developed on outer edge of first arch. Pebas, Equador. Prof. 

 J. Orton. Coll. 1873-77. Prof. E. D. Cope. 



GARMANINA subgen. nov. 

 Type Rhytiodus argenteo-fuscus Kjier. 

 Restricted to those species of Rhytiodus Kner with large scales, 

 about 50 to 60 in a lateral series. 



(Named for Prof. Samuel Garman, of Cambridge, Mass., author of 

 many excellent contributions to Ichthyology.) 

 Ehytiodus argenteo-fuscus Kner. 



Schizodon Sagittarius Cope, Proc. Amer. Philos. Soc. Phila., XVII, 1877-78 

 (May 17, 1878), p. 689. No. 21,474, A. N. S. P., type. Peruvian 

 Amazon. Prof. J. Orton. Coll. of 1877. 



Head 4f ; depth 5*-; D. in, 10; A. iii, 8; scales 47 in lateral hne to 

 base of caudal, and 5 more on latter; 7 scales obliquely back from 

 origin of dorsal to lateral line; 4 scales obliquely back from origin of 

 adipose fin to lateral line; 6 scales obliquely up from origin of anal to 

 lateral line; about 16 scales before dorsal; width of head 1|^ in its 

 length; depth of head over middle of orbit 2f ; least depth of caudal 

 peduncle 3; pectoral 1^; ventral H; depressed dorsal 4|; fourth anal 

 ray If ; snout 2| in head measured from tip of upper jaw ; eye about 4^ ; 

 interorbital space 2^. Body tapering evenly back from opposite 

 origins of dorsal and ventral. Predorsal region with an obtuse median 

 keel. Postdorsal region flattened. Preventral region rounded, except 

 region right at bases and just before ventrals, which is flattened. Post- 

 ventral region apparently rather rounded. Least depth of caudal 

 peduncle about half its length. Head depressed above and below 

 anteriorly, and with convex surface. Snout broad, rounded when 

 viewed above. Width of mouth about | of orbit. Teeth broadly 

 expanded or compressed. Maxillary reaching about to posterior nos- 

 tril. Anterior nostril in a short tube. Interorbital space broadly 

 convex. Gill-opening extending forward about opposite last fourth in 



