332 



PROCEEDINGS OF THE ACADEMY OF 



[June, 



shows traces of an interorbital band and a nuchal one extending down 

 just behind opercle. 



TETRAGONOPTERIN.E. 

 Cheirodon monodon (Cope). 



Chirodo7i monodon Cope, Proc. Amer. Philos. Soc. Phila., XXXIII, 1894 

 (January 5), p. 91, PI. 6, fig. 9. Nos. 21,561 (type) and 21,562, A. N. S. 

 P., cotypes. Brazilian province of Rio Grande do Sul. H. H. Smith. 



Edge of back rounded, except a httle before spinous dorsal and upper 

 surface of caudal peduncle where it is a little trenchant. Belly rounded. 

 Postventral region and lower surface of caudal peduncle a little trench- 

 ant. Each ramus of mandible elevated a little inside mouth. Tongue 

 rather large, flattened, moderately broad and free in front. Inter- 

 orbital space convex. Gill-opening extending forward nearly opposite 

 anterior margin of orbit. Rakers 12 + 12 on first arch, lanceolate, 

 and longest a little shorter than filaments, which are a little longer than 

 pupil. Isthmus narrowly triangular. Vent close in front of anal. 

 Color in alcohol pale brownish, back a little darker than lower surface, 

 and body everywhere more or less silvered. A pale or dull leaden- 

 brassy streak from above eye back to caudal. Fins all pale or immacu- 

 late brownish. Iris dull silvery. Length 1|| inches. Type. 



Fig. 21. — Cheirodon pulchcr (Steindachner). 



Cheirodon pulcher (Steindachner). Fig. 21. 



Tetragonopterus diaphanus Cope, Proc 

 1877-78 (May 17, 1878), p. 691. 

 (Part.) 



Amer. Pliilos. Soc. Phila., XVII, 

 Peruvian Amazon. Prof. J. Orton. 



