ANNOTATED LIST OF THE SPECIES 125 
Genus 34: PTERODORAS Bleeker 
Doras Valenciennes, in Humboldt, 1833, Rec. d’Obs. Zool. Anat., IT, 184; 
Eigenmann and Eigenmann, 1890, Occ. Papers Cal. Acad. Sei., I, 220; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 392. 
Pterodoras Bleeker, 1863, Nederl. Tijdsch. Dierk., I, 15, 16, and 86; 
Eigenmann, 1925, Trans. Amer. Phil. Soc., XXII, 311. 
Type: Doras granulosus Valenciennes 
Peru to Buenos Aires and Uruguay 
Similar to Megalodoras in the forward continuation of the adipose, and other 
characters, but differing in having many more and narrower scutes and a single air 
bladder, the latter with many diverticula along the side; head wide and depressed; 
caudal peduncle naked above and below; scutes 25-30, very narrow, and strongest 
over the anal; eye in anterior half of head; dorsal spine with about twenty hooks 
on the posterior border. 
76. PTERODORAS GRANULOSUS (Valenciennes) 
Doras granulosus Valenciennes, in Humboldt, 1833, Rec. d’Obs. Zool. Anat., IT, 184; 
Eigenmann and Eigenmann, 1890, Occ. Papers Cal. Acad. Sci., I, 229; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, IIT, 392. 
Pterodoras granulosus Bleeker, 1863, Nederl. Tijdsch. Dierk., I, 15; 
EKigenmann, 1925, Trans. Amer. Phil. Soc., XXII, 312, pl. i, figs. 1-3; pl. ii, fig. 6; pl. vin, 
figs. 1-5; text fig. 17. 
15659, 2, 95 and 117 mm., Maranon below Pastaza, Allen, October, 1920. 
15846, 2, 203 and 216 mm., Contamana, Rio Ucayali. Allen, July, 1920. 
15847, 14, 87-182 mm., Iquitos, Allen, September, 1920. 
15848, 4, 150-200 mm., Rio Puinagua, mouth Rio Pacaya, Allen, September, 1920. 
Genus 35: PLATYDORAS Bleeker 
Doras Lacépéde, 1803, Hist. Nat. Poiss., V, 116, carznatus and costatus; 
Cuvier and Valenciennes, 1840, Hist. Nat. Poiss., XV, 267; 
ERigenmann and Higenmann (part) 1890, Occ. Papers Cal. Acad. Sci., I, 220; 
EKigenmann (part) 1910, Rept. Princeton Univ. Exped. Patagonia, III, 392. 
Platydoras Bleeker, 1863, Nederl. Tijsch. Dierk., I, 16 and 86, costatus; 
Eigenmann, 1925, Trans. Amer. Phil. Soc., XXII, 315. 
Type: Doras costatus (Linnaeus) 
The Doradid genus of widest distribution, from our territory to the Guianas, 
the Orinoco, Sao Francisco, and Paraguay. 
Plated area extended to cover most of sides and leaving only a narrow naked 
zone across the back; first three scutes in contact with the dorsal plate; serrae of 
posterior surface of dorsal spine growing obsolete with age; mouth slightly inferior; 
air bladder double, of simple form, somewhat depressed anterior chamber, posterior 
chamber subconical. 
