60 CALIFORNIA ACADEMY OF SCIENCES. 



III. Dysichthys Cope. 



9. Dysichthys coracoides Cope. 



IV. Platystacus Blocli. 



Aspredo Linnaeus; Cotylepliorus Swainson; AspredinlcJithys 

 Bleeker. 



10. Platystacus cotylephorus Bloch. 



Sllurus hexadactylus Lacepede; Aspredo sex-cirrhis Cuv. & Val.; 



Aspredo spectrum Grouow. 

 Localities: Vigia; Para; Tajapuru. 



11. Platystacus nematophorus Bleeker. 



Aspredo nematophorus Gilntber. 



12. Platystacus aspredo (Linn). 



Platystacus Icevis Bloch; Aspredo hatrachus (Linnaeus). 

 Localities: Para; Arary. 



13. Platystacus sicuephorus (Cuv. & Vai.) 

 14r Platystacus filamentosus (Cuv. & Val.) 



15. Platystacus tibicen (Temminck). 

 Locality: Curuca, Rio Muria. 



PYGIDIDvE. ^ 



I. Nematogenys Girarcl. 



s 



1. Nematogenys inermis (Guichenot). 



N. nigricans tC- pallldus Pbilippi, 

 Localities: Curico; Santiago. 



II. Pariolius Cope. 



2. Pariolius armillatus Cope. 



III. Pygidium Meyen. 



TrichomycteriisYal.; Thrycomyderus Cuv. & Yal.; Thrico- 

 mycterus Girard. 



*The genus Ceiojms, pLiced in the Doradince, belougs here. It possesses 

 the peculiar modifications of the anterior vertebne characteiizing this family. 



