438 Bulletin ^7, United States National Museum. 



a. Anal rays about 76 ; scutes on belly 8 + 12. mucbonata, 714. 



aa. Anal rays about 67 ; scutes on belly 13 + 16. panamensis, 715. 



714. ODONTOGXATHUS MIICKONATA, Lacepede. 



Head 5 ; depth 4|. D. 11 or 12 ; A. 74 to 82 ; scutes 8 + 12. Eye as 

 long as snout, 3A in head in young. Maxillary tapering, extending in the 

 a^lult at least as far as interopercle, shorter and truncate in young. 

 Insertion o-f dorsal twice as far from eye as from base of caudal. Coast 

 of Guiana. (Giinther.) {mucronatus, with sharp points.) 



Odontofinulhtis niiicronatns, LAcfipEDE, Hist. Nat. Poiss., 221, pi. 7, fig. 2, 1799, Cayenne. 

 GHal)ioboln/> mua-otmlim, Cuvier & Valenciennes, Hist. Nat. Poiss., xxi, 91, 1848. 

 Pristigasler miicronatm, Gunther, Cat., vii, 462, 18G8. 



715. ODONTOGNATHUS PANAMEXSIJS (Steindachner). 



Head 5i ; depth nearly 4. D. 12 ; A. 67 ; scales 55 or 56. Eye equals 

 snout, 3f in head. Body very slender and compressed. Ui)per profile of 

 head strongly concave ; dorsal line before dorsal arched ; ventral outline 

 strongly arched ; base of anal straight. Mouth oblique; maxillary pro- 

 duced in a slender process, which reaches beyond gill opening; a thin 

 accessory bone, with a bluntish keel on the maxillary, half hidden when 

 the mouth is closed. Teeth small, short, mostly in one row. Top of head 

 narrow, with five ridges. Pectoral longer than head by an eye's diameter, 

 the first ray broad. Dorsal small, twice as far from gill opening as from 

 base of caudal ; caudal as long as head ; ventral' scutes 13 + 16 ; scales 

 caducous. Panama. Length 8 inches. (Steindachner.) 



Pristigasler [Odontof/iKitliiis) 2iMiamensis, Steindachner, Ichth. Beitr., v, 24, 1876, Panama. 



217. PRISTIGASTER, Cuvier. 



Pruiligaster, Cuvier, Regne Animal, Ed. 1, 176, 1817, {cayaims). 



This genus ditters from Opisthopterus in the deeper body, the ventral 

 ridge being very prominent and convex, and especially in the position of 

 the dorsal. This fin is larger in Pristigaster than in related genera, and is 

 inserted near the middle of the length of the body, before the anal. One 

 species know, from South America. (TrpiaTrig, a saw; yaarijp, belly.) 



716. PRISTIGASTER CAYASUS, Cuvier. 



Head 4 ; depth 2. D. 15 ; A. 46 to 52. Front of dorsal much nearer tip 

 of snout than base of caudal ; upper caudal rays produced in filaments in 

 adult, these longer than the fin itself. Abdominal profile subcircular in 

 the adult. Scutes 32. Color silvery. Length 4 inches. Coast of Guiana 

 and northern Brazil. (Cuvier & Valenciennes. ) (Cayanus, from Cayenne. ) 



Prisligaster cayamis, CuviBR, R6gne Animal, Ed. 1, pi. 10, fig. 3, 1817, Cayenne; Cuvier & Val- 

 enciennes, Hist. Nat. Poiss., xx, 334, 1847 ; Gunther, Cat., vii, 463, 1868. 



Pristigasler murtii, A0AS.SIZ, Spix, Pise. Brasil., 5h, 1829, Brazil. 



Prisligaster phaeton, Cuvier Jt Valencienhes, Hist. Nat. Poiss., xx, 338, 1847, mouth of Ama- 

 zon. 



