VOL. XIV."] 



18U1. J 



PKOCEEDINGS OF THE NATIONAL MUSEUM. 



15 



Y. 



Genera peculiar to the western slopes of Peru, Ecuador, and Colombia: 



1 Lebiasina 1 sp. 



2. Saccodon 2 sp. 



3. Pseudocbalceus lap. 



4. Gastropterus 1 sp. 



Average number of species to each genus, 1.25. 



VI. 



Genera peculiar to the Amazons and the region to the north of them, 

 especially the Guianas. Those marked with an asterisk (*) have rep- 

 resentatives in the Eio San Francisco : 



/ . 



8. 



9. 

 10. 

 1!. 

 1>. 

 13. 

 14. 

 lo. 

 IG. 

 17. 

 18. 

 19. 

 20, 

 21. 

 22, 



23. 



Bunocepbalus 



Aspredo 



CalloiDbysns 



Pbractocepbalus 



Sorubimicbtby3 



Hemidori.s* 



Tracbelyopterus 



Centromocblus 



Aucbenipterus 



Hypopbtbabuus 



Farlowella 



Hypoiitojio'iia 



Pauaque 



Pterygoplicbtbys* 



Pyrrbulina 



Cbilodus 



Nannostomus 



Piabuciua 



Odontostilbe 



Cbalceus 



Creatochaues 



Creagrutus* , 



Upper courses of rivers. 

 Piabuca 



7 sp. 

 (5 sp. 

 1 -sp. 

 1 sp. 

 3 s)). 



13 sp. 

 2sp. 

 5 sp. 

 3 sp. 



1 sp. 

 G sp. 

 3 sp. 



3 sp. 



8 sp. 



9 8p. 



2 sp. 



5 sp. 



4 sp. 



2 sp. 

 2sp. 



3 sp. 



4 sp. 



2 sp. 



24. 

 25. 



26. 

 27. 



28. 

 29. 

 30. 

 31. 



3-2. 

 33. 



34. 

 35. 

 36. 

 37. 

 3-5. 

 3J. 

 40, 

 41, 

 42, 



Anacyrtus 



Ka?stes 



Oue species in Guatemala. 



Exodou 



Xipbostoma 



Hydiolycus 



Cyuodou 



Crenncbus 



Mylesinius 



Boiiu<laries ot distributiou not 



well defined. 



Pygopristis 



Electropborus 



Soutberu boundaries not well 



defined. 



Rbampbosteruarcbus 



Kbauipbicbtbys 



Uracbyrbanipbicbtbys 



Osteoglossum 



Potamorrbapbis 



Plagiosciou 



Cicbla 



Cba^tobraucbus 



Colomesus 



C sp. 

 2 sp. 



1 sp. 

 6 sp. 

 4 sp. 



2 sp. 

 1 sp. 

 1 sp. 



2 sp. 

 1 sp. 



5 sp. 

 Ssp. 

 5 sp. 

 1 sp. 

 1 sp. 

 4 sp. 

 4 sp. 

 4 sp. 

 1 sp. 



Average number of species 



to each genus, 



3.5. 



vir. 



Genera peculiar to the Amazons (Amazon, Solimoens, Maranon) and 

 their tributaries. 

 Those genera found in but two of tlie rivers are included here : 



1. Lepidosireu 1 sp. 



2. Piramutana 1 sp. 



3. Platyuematicbtbys 2 si>. 



4. Sciades 2 sp. 



5. Aucbeniptericbtbys 2 sp. 



G. Ei)apterus 2 sp. 



7. Vaudellia 2 sp. 



8. Pareiodon 2 sp. 



9. Ilemiodouticbtbys 1 si>. 



10. Parancistrus 3 sp. 



11. Acantbicus 3 sp. 



12. Decapogon 1 sp. 



