378 



PATAGONIAN EXPEDITIONS I ZOOLOGY. 



Narcine corallina Carman; Narcine 

 umbrosa Jordan; Torpedo bancrofti 

 Griffith; Narcine nigra Dumeril; 



Torpedo pictus Gronow. 

 Habitat: Pensacola and Key West to 

 Brazil, entering rivers. 



Suborder MASTICURA. 

 Family MYLIOBATIDJE. 



MYLIOBATIS Dumeril. 



Holorhinus Gill. 



Type : Raja aquila Linnaeus. 



Range : Warm seas. 

 I. Myliobatis aquila (Linnaeus), 



Giinther, VIII, 489 

 Habitat : All warm seas ; La Plata. 



Family DASYATID^. 



PARATRYGON Dumeril. 



Disceus Garman. 



Type: Trygon aiereba Cuvier. 

 Range that of the single species, 

 Ai. Paratrygon strongylopterus (Schom- 



burgk), Gunther, VIII, 476. 



Trygon aiereba Dumeril; Trygon or- 



bicularis Gunther. 

 Habitat: British Guiana; Amazons. 



POTAMOTRYGON Garman. 



Type : Pastinaca humboldtii Roulin. 

 Range : Fresh waters of South America. 

 I. Potamotrygon brachyurus (Gunther), 



Gunther 1880, 8. 

 Habitat: La Plata. 



A2. Potamotrygon humboldtii (Roulin). 

 Trygon hystrix Miiller & Henle. 

 f Trygon garrapa Schomburgk. 

 Habitat: Rivers from the La Plata to 

 the Orinoco; Paraguay, Rio 

 Branco; Orinoco at Apure. 

 3. Potamotrygon d'orbignyi (Castelnau), 



Gunther, VIII, 484. 

 Habitat: Orinoco. 



Garman considers d'orbignyi and magdaleniz syn- 

 onymous with humboldtii. 



A4. Potamotrygon reticulatus Gunther, as 



hystrix Gunther, VIII, 482. 

 Habitat: Surinam; Santarem. 

 5. Potamotrygon magdalence 1 (Steindach- 



ner), Steindachner, 1878, 56. 



Habitat : Rio Magdalena. 

 A6. Potamotrygon motor o (Miiller & 



Henle), Gunther, VIII, 484. 



Trygon henlei Castelnau ; Trygon gar- 

 rapa Schomburgk; Tccniura miilleri 

 and henlei Castelnau. 

 Habitat: Rio Cuyaba; Rio Branco. 

 A 7. Potamotrygon dumerilii (Castelnau), 



Gunther, VIII, 484. 

 Habitat : Araguay ; Tocantins ; Rio 

 Crixas; Paraguay. 



ELLIPESURUS Schomburgk. 



Type : Ellipesurus spinicauda Schom- 

 burgk. 



Range that of the single species. 

 Ai. Ellipesurus spinicauda Schomburgk, 



Gunther, VIII, 472. 

 Habitat: Rio Jurua; Rio Branco. 



