8 CALIFORNIA ACADEMY OF SCIENCES. 



Cetopsin.e — Amazons from Rio Cupai to its upper 

 courses; Guayaquil (Irisanga?). 



Pygidin.e — Mountain streams from Chile to Col- 

 ombia; Amazons eastward to Cudajas; mountain 

 streams of Southeastern Brazil and center of 

 Argentine Republic. 



Stegophilin^ — Brazil, chiefly in headwaters of 

 rivers. 



VI. Argiid^ — Andes of Peru, Ecuador and Colombia. 



VII. LoRiCARiiDiE — Eastern slopes of South America 

 from the Argentine Republic to Central America; 

 western slopes of Ecuador and Colombia. 



Loricariin^ — La Plata to the Orinoco and Rio Mag- 



dalena; both slopes of Panama. 

 Hypoptopomin.e — Rio Janeiro and Rio Parahyba; 



Amazon from Rio Negro to Rio Ambyiacu; 



Venezuela. 

 Plecostomin.^ — Cordova; Rio Plata to Rio Magda- 



lena; Avestern slopes of Ecuador; both slopes of 



Panama. 



VIII. Callichthiid.e — Rivers between La Plata and 

 Orinoco; Amazons to Nauta. 



analysis of the AMERICAN FAMILIES AND SUBFAMILIES 

 OF NEMATOGNATHI. 



a. Air bladder well develop'ed, simple or with trans- 

 verse constrictions (except in Ageneiosus); lying free 

 in the abdominal cavity. Mouth terminal, teeth 

 villiform, conical, incisor or molar-like; intestines 

 short, arranged in longitudinal folds. Body naked or 

 with a single series of lateral plates. Diaphragm mem- 

 branaceous. Tip of scapular process touching basi 

 occipital. 



