DEC. 28,1916. FISHES OF PANAMA MEEK AND HILDEBRAND. 231 



of this region, during the rainy season when the streams are high, often 

 drag their canoes from the head waters of one basin to those of the other, 

 and inasmuch as the fishes of the two streams are much alike it seems 

 very probable that within comparatively recent times a gap remained 

 somewhere along this water shed. 



The following species were obtained in the Rio Tuyra Basin: Family 

 Siluridai; Ageneiosus caucanus, Pimelodella chagresi, Pimelodus clarias 

 punctatus, Rhamdia wagneri, Trachycorystes amblops: Family Lori- 

 cariid<s; Leptoancistrus canensis, Lasiancistrus planiceps, Chatosto- 

 mus fischeri, Ancistrus spinosus sp. nov., Plecostomus plecostomus, 

 Loricaria fimbriata, Loricaria capetensis, Loricaria filamentosa latiura, 

 Loricaria variegata, Oxyloricaria citurensis, Oxyloricaria panamensis: 

 Family Pygidiida; Pygidium striatus: Family Cyclopidcs; Cyclopium 

 pirrense: Family Characidce; Apareiodon dariensis, Astyanax ruberrimus, 

 Astyanax fasciatus, Bryconamericus emperador, Brycon argenteus, Brycon 

 striatulus, Gephyrocharax atricaudata, Creagrutus simus, Curimatus 

 magdalencB, Hemibrycon dariensis sp. nov., Hoplias malabaricus, Lucio- 

 charax beani, Piabucina festce, Phanagoniates macrolepis, Pseudocheirodon 

 affinis gen. et sp. nov., Compsura gorgona, Rceboides occidentalis sp. nov., 

 Thoracocharax maculatus: Family Gymnotida; Eigenmannia virescens, 

 Hypopomus brevirostris, Siernarchus rostratus, Sternopygus dariensis sp. 

 nov.: Family Pceciliidce; Mollienisia caucana, Priapichikys dariensis t 

 Priapichthys tridentiger cana: Family Cichlida; Mquidens coeruleo- 

 punctatus, Cichlasoma calobrense, Cichlasoma tuyrense, Cichlasoma umbri- 

 ferum, Geophagus crassilabris: Family Gobiidce; Awaous transandeanus, 

 Philypnus maculatus. 



Among the family Silurida there are again the two species, Pimelo- 

 della chagresi and Rhamdia wagneri, occurring everywhere in Panama. 

 Ageneiosus caucanus is common to the Rio Tuyra and the Rio Atrato, 

 and the other two species of this family, while not identical, are very 

 closely related to Atrato forms, from which they are slowly changing 

 under the different environment. The genera Ageneiosus, Pimelodus 

 and Trachycorystes all reach the northern limit of their range in the Rio 

 Tuyra. 



Under the family Loricariida, there is again the widely distributed 

 species Plecostomus plecostomus, and Ch&tostomusfischeri, the latter occur- 

 ring on both slopes of Panama and quite surely also in Colombia. Lori- 

 caria fimbriata and Loricaria filamentosa latiura also occur on the Atlantic 

 slope of Colombia and Oxyloricaria panamensis occurs on both slopes 

 of Colombia and in Ecuador and reaches its northern limit in the Rio 

 Bayano. Ancistrus spinosus sp. nov., Loricaria variegata and Oxylori- 

 caria citurensis also are found in the Rio Bayano. Leptoancistrus 



