36 BULLETIN 95^ UNITED STATES NATIONAL MUSEUM. 



Pygidium punctulatum Staeks, Fishes from Ecuador and Peru, Proc. U. S. 



Nat. Mus., vol. 30, p. 771, 1906. 

 Pygidium dispar Tschudi var. punctulaUim Steindachnee, Herpet.-ich- 



thyol., Ergebnisse einer Reise nach Sudamerika, Denkschr. Akad. Wiss. 



Wien, vol. 72, 1902, p. 49 ; Rio Chillon, near Lima. 



Two specimens, field No. 265, 14 and 15.4 cm. in length; nine 

 specimens, field No. 213, 5.4 to 9.4 cm. in length, from the Rimac 

 River below Lima; and one specimen, field No. 426, 22.8 cm. in 

 length, from the Rimac near Lima. 



Head 5.12 in length; depth 6.5; eye 10 in head, 3 in interocular 

 space; snout 1.3 in head; interocular space 3.16; D. 12, only seven 

 of which are branched, only two of the simple rays discernible with- 

 out dissection; A. 9, only five of which are branched, and only one 

 of the simple rays discernible without dissection. Body robust, much 

 compressed posteriorly, least depth of caudal peduncle 1.73 in head; 

 head depressed, its breadth 1.22 in its length; distance from tip of 

 snout to insertion of dorsal 1.6 in length ; insertion of dorsal slightly 

 posterior to base of ventrals; distance from tip of snout to insertion 

 of anal 1.35 in length, insertion of anal in vertical from posterior 

 base of dorsal; ventrals short, barely reaching vent, 1.90 in head; 

 upper pectoral ray produced into a long filament, length of fin with- 

 out filament, 1.58 in head. 



Color in alcohol : Lavender ; body covered with rather large, round, 

 brownish black spots, those on top of head and base of caudal smaller 

 and more numerous. Description based on a specimen 22.8 cm. long. 



The validity of this species seems questionable, as it appears to 

 differ from P. dispar in little but color, and the variability of colora- 

 tion in our examples seems to indicate that this character has little 

 value. In the two larger specimens in our collection many of the 

 spots on the sides of the body are as large as or larger than the 

 eye; in the smaller specimens the size of the spots is variable, in 

 some they are mere points thickly sprinkled over the entire body 

 and in others considerably larger and in correspondingly smaller 

 numbers. 



46. PYCmiUM PARDUM (Cope). 



Trichomycterus pardus Cope, Proc. Acad. Nat. Sci. Phila., 1874, p. 132; 



Proc. Amer. Philos. Soc, 1877, p. 45 ; Jequetepeque ; Callao Bay. 

 Pygidium pardum Eigenmann and Eigenmann, Nematognathi, 1890, p. 337. 



47. PYGIDIUM QUECHUORUM Steindachner. 



Pygidium quechuorum Steindachner, Herpt.-ichthyol., Ergebnisse einer 

 Reise nach Sudamerika, Denkschr. Akad. Wiss. Wien, vol. 72, 1902, 

 p. 49, pi. 4, fig. 3, 3a; Rio Chile, near Arequipa, Peru. 



