SOUTH AMERICAN NEMATOGNATHI. 263 



head exposed, granular. Dorsal plate coalesced with the 

 occipital process. Humeral process present. Gill-mem- 

 hranes confluent with the skin of the isthmus. Teeth 

 villiform, none on the vomer. 



203. Trachelyopterichthys tseniatus. 



Tr(u:hiihjoi)lerux t<tnhituti Kiier, 8B. Ak. Wieu, xxvi, 434, pi. viii, 



fig. 26, 1857 (Eio Gnapore); Gtiuther, v, 198, 1864 (copied); 



Steindachner, Fhissf. SUdamerika's, iii, 4, 1881 (Rio Gnapore; 



Teffe). 

 Trachelyopierkhthys trvniatus Bleeker, Nederl. Tijdsclir. Dierkuude, 



i. 111, 186.3 (name only); Eigeam. & Eigeum. Proc. Cal. Acad. 



2d Ser. i, 157, 1888 (Teffe). 

 Habitat: Solimoens and tributaries. 



Body elongate, compressed. Head short and wide, its 

 width greater than its length, its depth slightly less than 

 its length; bones of the head exposed, coarsely granular; 

 sutures distinct; dorsal plate widely forked behind. Fon- 

 tanel elongate. 



Eye small, 5 in the head, Sh in the interorbital. 



Maxillary barbel reaching tip of humeral process; 

 mental barbels short, little longer than the eye; post- 

 mentals reaching base of pectorals. Snout short, rounded; 

 jaws equal; teeth all villiform. 



Distance of dorsal spine from tip of snout 4-4j in the 

 length; dorsal spine sharply granular in front, smooth 

 posteriorly; its length IJ in the head. 



Caudal obliquely rounded. 



Base of the anal very long, 2|-2y in the length. 



Ventrals very large, reaching the anah 



Pectoral spine somewhat longer than the head, gran- 

 ular on its lower, finely stirate on its upper surface. Hu- 

 meral process extending beyond middle of pectoral spine. 



Pectoral pore present. 



Coffee-colored, all the fins dusky, especially near their 

 tips. 



Head 6^.; depth 5|-6i; D. I, 4; A. 53; P. I, 8; V. 15-16. 



Three specimens .13-. 15 m. Teffe. L. Agassiz. 



