DEC. 28, 1916. FISHES OF PANAMA MEEK AND HILDEBRAND. 359 



to 4.85 in head; eye 5.13 to 6.4; interorbital 3.65 to 6; mouth rather 

 large, oblique; the lower jaw projecting; maxillary scarcely reaching 

 middle of eye in young, reaching past this point in adult, 2.44 to 3.25 

 in head; cheeks with partly embedded scales; chin, cheeks and snout 

 with rows of pores, forming a net-work, these most distinct in young; a 

 concealed preopercular spine, directed downward and forward; teeth 

 small, pointed, in bands; gill-rakers undeveloped; gill-membranes 

 attached to the isthmus; scales small (average in lateral series, for 16 

 specimens, 64+), about 18 longitudinal rows between base of second 

 dorsal and anal, those on anterior part of body more or less embedded, 

 but less so than in E. picta; scales on posterior part of body distinctly 

 ctenoid, those on anterior part of body and abdomen smooth; origin of 

 first dorsal midway between end of snout and tips of rays of second 

 dorsal, the spines short and weak, reaching second dorsal when deflexed; 

 origin of second dorsal an eye's diameter in advance of origin of anal; 

 caudal fin with small scales on base, its margin convex; anal fin similar 

 to second dorsal; ventral fins rather small, inserted under base of 

 pectorals; pectoral fins moderate, reaching well beyond tips of ventrals, 

 1.3 to 1.54 in head. 



Color rusty brown above, pale brown below; rows of scales every- 

 where with dark lines. Dorsal fins and sometimes the caudal and anal 

 also with dark and yellow spots or bars; pectoral and ventral fins yellow- 

 ish green. 



This species is represented by 16 specimens, ranging from 45 to 125 

 mm. in length. It was found in the lower courses of the Rio Chagres 

 and its tributaries, small coastal streams at Porto Bello and in the upper 

 courses of the Rio Trinidad, It is much less abundant and apparently 

 reaches a smaller size in Panama than its Pacific coast congener. It 

 was always found in strictly fresh water. 



Habitat: Atlantic coast and rivers, from Florida to southern Brazil, 

 and the West Indies. 



86. Eleotris isthmensis sp. nov. 



Type No. 8951, F. M. N. H.; length 85 mm.; Mindi, Canal Zone, 

 Panama. 



Head 2.85 to 3.25; depth 4.2 to 5.4; D. VI-I, 8; A. I, 8; scales 44 to 



54- 



Body elongate, anteriorly subcylindrical, posteriorly compressed; 

 head somewhat depressed above, the profile slightly concave over eyes; 

 snout broad, 4.1 to 5 in head; eye 4.22 to 5.8; interorbital 3.8 to 5.2; 

 mouth rather large, oblique; the lower jaw projecting; maxillary reach- 

 ing to or past middle of eye, 2.6 to 3.3 in head; cheeks with partly em- 



