EIGENMANN: THE PYGIDHDjE, A FAMILY OF SOUTH AMERICAN CATFISHES. 275 



Nevada dc Santa Marta for the University of Michigan, and Mr. E. B. William- 

 son secured specimens for me in the Sierra Nevada, and in other places in Colombia. 



Mr. J. D. Haseman, who collected for the Carnegie Museum, secured many 

 species, especially between the Rio Sao Francisco and Buenos Aires, as well as in 

 the upper Paraguay basin and in the Amazon. 



At one time or another I have examined all of the seventy-one species pre- 

 served in American Museums, fifty-eight species in the Indiana University Museum 

 and the Carnegie Museum being under my immediate charge. Nine of the eigh- 

 teen known genera and forty-three of the ninety-five known species were described 

 by me during the course of my study. 



I have attempted to collect what is known of the members of the family. I 

 hope the result will help the next one who undertakes the study of the group and 

 stimulate the collection of additional specimens and facts of the commensal or 

 parasitic members of the family. 



The Zoological Position of the Pygidiidce. 



Phylum PISCES Artedi. 



Class TELEOSTOMI Bonaparte. 



Superorder OSTARIOPHYSI Sagemehl. 



Order PLECTOSPONDYLI Cope. 



Family: Pygidiidce Eigenmann & Eigenmann. 



Subfamilies : 



Nematogenyin^e Gtinther. 

 Pygidiin^e Eigenmann & Eigenmann. 

 Pareiodontin^e Eigenmann. 

 Stegophilin,e Gtinther. 

 Vandelliin^e Eigenmann. 

 Tridentin,e Eigenmann. 



Synonymy. 

 = Siluroidei Trichomycterifvrmes Bleeker, Nederl. Tijdschr. Dierk., 1, 1863, p. 112. 

 > SiluridoB Opisthopterce Gunther, Cat. Fish. Brit. Mus., V, 1864, p. 4 and p. 271. 



< Siluridce Branchicolce Gunther, I. c, p. 4 and p. 276. 



= Trickomycteridce Gill, Arrangement of Families of Fishes, 1872, p. 19. 



< Pygidiidce Eigenmann & Eigenmann, Am. Nat., July, 1888, p. 649; Occasional 



Papers California Academy Sciences, I, 1890, p. 316. 



< Pygidiidce Gill, Mem. Nat. Acad. Sci., VI, 1893, p. 132. 



