THE AMERICAN TETRAGONOPTERINAE. 



307 



Specimens examined. 



There seems to be no doubt but that Tetragonopterus belizanus 5224 and 

 5225, Museum Histoire Naturelle, 12 specimens, and T. finilimus, 5223, Guate- 

 mala, 2 specimens, are typical A. aeneus. They have A. 27, 26, 27, 28, 30. 



This species differs from typical A. fasciatus in the thicker body, more 

 slender caudal peduncle, and in having usually 2 maxillary teeth. 



For the details of the anal fin see the table (p. 297). While there is no diffi- 

 culty in distinguishing this species from A. macrophthalmus it is impossible to as- 

 sign any character to it that will at all times distinguish it from typical A. fasciatus. 



54. AsTYANAX MEXiCANUS (Filippi). ' 

 Plate 49, figs. 4 & 5. 



Tetragonopterus mexicanus Fiuppi, Rev. et mag. zool., 1853, p. 166; Steindachnbk, Ichthyol. notizen, 

 1869, 9, p. 11, pi. IV, figs. 1-4 (Lake Mexico; Izucar); Eigenmai^n & Eigenmann, Proc. U. S. 

 N. M., 1891, 14, p. 55; Ulrey, Ann. N. Y. acad. sci., 8, 1895, p. 282; Jord.4.n & Evermann, Bull.' 

 47 U. S. N. M., 1896, 1, p. 335; Jordan & Snyder, Bull. U. S. fish comm., 1900, 19, p. 125 (Rio 

 Ixtla; Puente de Ixtla; Morelos); Meek, Field Columbian mus. Publication, 1902, 3, p. 86, 

 (Puente de Ixtla; Balsas; Cuicatlan; Venta Saladad) ; 1904, 93, (Rio Balsas and Rio Tehucan to 

 the Rio Grande). 



As(!/anax?«exicanMs Fowler, Proc. Acad. nat. sci. Phil., 1906, p. 345 (Monterey; Rio Ixtla; Rio Verde); 

 Eigenmann & Ogle, Proc. U. S. N. M., 1907, 33, p. 25 (Te.xas; Rio Nueces; Devil's River; Rio 

 Leona; Comanche Springs; Ehn Creek; Brownsville; Rio Seco; Caderita; China near Leon; 

 Stockton; Rio Grande; Matamoras; Las Moras; Fort Clark; Monterey; Mexico); Eigenmann, 

 Rept. Princeton univ. exped. Patagonia, 1910, 3, p. 433. 



Aslijanax argeniaius Baird & Girard, Proc. Acad. nat. sci. Phil., 1854, 7, p. 27; Girard, U. S. & Mex. 

 bound: surv., 1859, p. 74 (Rio Neuces; Rio Leona; Zoquito; Comanche Springs; Ehn Creek; San 

 Felipe; Devil's River; Brownsville; Mouth of Rio Grande; Rio Sabinal); Gunther, Cat. fishes 

 Brit, mus., 1864,6, p. 380; Garman, Bull. M. C. Z., 1881, 8, p. 92 (Tributaries of Lago de Muert6 

 and springs near Monclava). 



