EIGENMANN: THE FRESHWATER FISHES OF BRITISH GUIANA 21 



73. Cenlrarchus f vittatus Schomburgk, p. 161, Loc? = ? 



pi. 14. 



74. Cenlrarchus f? rostratus Schomburgk, p. Rio Negro. 4.4 inches. = Acaropsis nassa 



163, pi. 15. (Heckel). 



*75. Cenlrarchus f cyanoplerus Schomburgk, p. Essequibo. 3 in. = ? Cichlasoma bimaculatum 



165, pi. 16. (Linnaeus). 



76. Pomotis ? fasciatus Schomburgk, p. 169, Rios Padauiri and Negro. 8.5 in. 



pi. 17. 



*77. Pomotis ? bono Schomburgk, p. 171, pi. 18. Al! rivers, and in pools and marshes. 6.5 in. = 



Mqitidens tetramerus (Heckel). 



78. Gymnotus electricus Linnaeus, p. 173, pi. Rio Negro. = Electrophorus electricus (Linnaeus). 



18. 



79. Gymnotus fasciatus Pallas, p. 174, pi. 19. Rio Branco. = Gymnotus carapo Linnaeus. 



80. Trigon histrix f D'Orbigny, p. 180, pi. 20. River Roowa. 12 inches. = Potamotrygon hys- 



trix (Miiller & Henle). 



81. Trygon garrapa Schomburgk, p. 182, pi. Rio Branco. = Potamotrygon hystrix (Miiller & 



21. Henle). 



82. Trygon strongylopterus Schomburgk, p. Rio Branco. = Paralrygon strongylopterus 



183, pi. 22. (Schomburgk). 



83. Elipesurus spinicauda Schomburgk, p. Rio Branco. 



184, pi. 23. 



84. Silurus parkeri Trail, p. 188, pi. 24. = Sciadeichthys parkeri (Trail). 



The brother, Richard Schomburgk, in the expeditions which have been men- 

 tioned, ascended the Demerara River to near the "Great Fall," He also threaded 

 the Pomeroon, Waini, and Barima Rivers, which discharge their waters west of 

 the Essequibo. He ascended the Essequibo to the Rupununi, following the latter 

 to near its sources. From Pirara he ascended the Takutu to its source and de- 

 scended it to Fort San Joaquin, whence he went to Roraima. His last collections, 

 made on the trip to Roraima, were aU lost. 



An account of his journeys was published in two volumes under the title 

 "Reisen in British Guiana in den Jahren 1840-1844 im Auftrag Sr. Majestat des 

 Konigs von Preussen." His collections were enumerated in a third volume. The 

 new fishes were largely described in the "Horae Ichthyologicse," by Miiller & 

 Troschel, who also prepared the account of the fishes in this third volume. He gives 

 many notes on the habits of the fishes in the first two volumes. Miiller & Troschel 

 enumerate one hundred and forty-one species as represented in his collections. 10 

 Most of these I had an opportunity of examining in the Zoological Museum in 



10 To these Schomburgk adds ten species known to him, but not recognized by Miiller and Troschel. 

 Some of these, like Myletes pacu, as Schomburgk himself noted, were given by Miiller & Troschel under other 

 names. 



