[Cope. '^"^ Aug. 19, 



fin elevated, a little behind the line of the origin of the ventrals. The 

 maxillary extends to near the line of the anterior margin of the orbit. 

 The anterior radii of the anal fin are elongate. Total length .075 M.. 

 Length of anterior dorsal rays .018 M. ; length of anal rays .013 M. 



A silver lateral band with a posthumeral and basal caudal spots, the 

 former very distinct. 



This species has much the shape of an Abramis ; its form is deep, 

 rather abruptly contracted at the extremities, and the supraoccipital 

 region is slightly concave. Allied to the T. abramis of Jenyns. 



Para. Mus. J. Carson Brevoort. 



Tetragonoptekus hauxvfelliakus. Cope. 



Radii D. 11 ; A. 47; squamation 9-10—47—10-11. Depth of body 2.2 

 times in length, exclusive of caudal fin. Profile above concave ; end of 

 muzzle convex. Interorbital width greater than diameter of orbit ; eye 

 three times in head. No teeth on the maxillary, which extends only to 

 the line of the anterior margin of the orbit. Caudal peduncle contracted. 

 Color silver olive, with silver white band on side, and indistinct humeral 

 and caudal spot. Total length .056 M. 



This is a deep bodied species, with more than usually distinct lateral 

 silver band. Its anal radii are more numerous than in any other species, 

 except the T. spilurus C. V., which differs in having teeth on the max- 

 illary bone, etc. 



Dedicated to John Hauxwell, a successful naturalist and explorer, from 

 whom most of the species here described were procured. 



Pebas, Equador. 



Tetragonopterxjs pectinatus. Cope. 



Radii D. 10, A. 41 ; scales 4-5 — 41 — 6. Form elongate, fusiform, com- 

 pressed ; depth into length without caudal 2.75 times; length of head 

 nearly four times in the same. Interorbital width equal diameter orbit ; 

 diameter of eye one third length of head. Maxillary bone elongate, ex- 

 tending to below middle of pupil, fui'nished with minute teeth throughout 

 the length of its anterior margin. Profile straight, convex between 

 orbits, muzzle projecting beyond mandible. Dorsal rays prolonged ; 

 anterior anals also moderately elongate. The origin of the dorsal is ex- 

 actly over that of t)ie anal. 



A narrow silver green band on the posterior half the body ; no caudal 

 spot ; humeral spot half way between lines of operculum and dorsal first 

 ray. Total length .045 M. 



This is a peculiar species, resembling technically only the T. artedii of 

 Cuv. and Val. as described by Giinther. This is a more elongate fish, 

 with smaller eye, and other characters. The complete dentition of the 

 maxillary bone is unusual in the genus. 



From Pebas, Equador. Hauxwell's collections. 



