3$8 FIELD MUSEUM OF NATURAL HISTORY ZOOLOGY, VOL. X. 



Color bluish black above, paler below; ventral surface of head and 

 body marbled or spotted with light and dark markings. These mark- 

 ings become obscure in large examples (250 mm. and more in length). 

 No dark lines along the rows of scales. Fins all with dark and pale 

 markings, forming alternating dark and pale bars, these also become 

 obscure and disappear in large individuals. 



This species is represented by 56 specimens, ranging from 60 to 440 

 mm. in length. It is common, but not abundant, in the lowland streams 

 on the Pacific coast of Panama eastward to the Rio Bayano, but it was 

 not taken in the Rio Tuyra. 



The alimentary canal is short, no pyloric cceca; air bladder thin, 

 adnate to the back. One specimen, 370 mm. in length, had swallowed 

 a fish (Philypnus maculatus) 210 mm. in length. The head of this mor- 

 sel was at the vent and partly digested, and the tail was visible in the 

 mouth. 



This species is closely related to E. pisonis, from which it apparently 

 differs only in the characters mentioned in the key. 



Habitat: West coast and streams, from California to Panama and 

 Ecuador. 



85. Eleotris pisonis (Gmelin). 



Gobius pisonis Gmelin, Linn. Syst. Nat., 1788, 1206 (based on Eleotris 



capite plagioplateo Gronow, Mus. Ichth., II, 1757, 168, which in 



turn was based on A more pixuma Marcgrave & Piso, Hist. Brasil., 



IV, 1648, 166 (Brazil)). 

 Gobius amorea Walbaum, Artedi Piscium, III, 1792, 205 (based on 



Eleotris capite plagioplateo Gronow). 

 Eleotris pisonis Schneider, in Bloch's Syst. Ichthyol., 1801, 68; Eigen- 



mann & Fordice, Proc. Ac. Nat. Sci. Phila., 1885, 75; Jordan & 



Evermann, Bull. U. S. Nat. Mus., XLVII, 1898, 2200; Regan, Biol. 



Cent. Amer., Pisces, 1905, 7. 

 Eleotris gyrinus Cuvier & Valenciennes, Hist. Nat. Poiss., XII, 1837, 



220, PI. 356 (Martinique; San Domingo; Surinam). 

 Culius perniger Cope, Proc. Am. Phil. Soc., 1870, 473 (Brazil). 

 Culius belizianus Sauvage, Bull. Soc. Philom. Paris, 1879, 55 (Belize; 



Cayenne). 



Head 2.9 to 3.23; depth 4.12 to 6; D. VI-I, 8; A. I, 8; scales 59 

 to 68. 



Body elongate, anteriorly subcylindrical, posteriorly compressed, a 

 little deeper and somewhat more rubust than in E. picta, this difference 

 being most evident in a comparison of specimens of like size; head some- 

 what depressed above, the profile concave over eyes; snout broad, 3.85 



