362 Field Museum of Natural History — Zoology, Vol. X. 



Body elongate, anteriorly subcylindrical, posteriorly compressed; 

 head as wide as deep, its width at preopercular margin 1.7 to 2 in its 

 length, the upper profde straight or slightly convex ; snout rather broad, 

 3.7 to 4.1 in head; eye moderate, partly superior, 4.15 to 5.86; inter- 

 orbital narrow, 8.75 to 10; mouth large, oblique; the lower jaw strongly 

 projecting; maxillary reaching to or past middle of eye, 2 to 2.5 in head; 

 teeth all small, pointed, in a broad band in each jaw; gill -membranes 

 rather narrowly connected with the isthmus, the opening extending 

 forward to vertical from posterior margin of eye; scales rather large, 

 thin, weakly ctenoid, none on head, chest or predorsal region, 7 or 8 

 rows between base of second dorsal and base of anal ; origin of first dorsal 

 about midway between tip of snout and base of last ray of second dorsal, 

 the spines weak, the longest reaching opposite first or second ray of 

 second dorsal when deflexed; origin of second dorsal slightly in advance 

 of origin of anal, the rays rapidly increasing in length posteriorly, the 

 longest reaching base of caudal in our largest examples, proportionately 

 shorter in the smaller ones; caudal fin with only a few scales at base, 

 the margin rounded; anal fin similar to second dorsal; ventral fins rather 

 long, reaching nearly or quite to vent; pectoral fins reaching opposite 

 origin of anal, i.i 2 to 1.38 in head. 



Color olivacious; back and sides with dark points and blotches; 4 or 

 5 saddle-Hke bars on back; a series of elongate blotches on median Ime 

 of side; caudal spot present. Dorsals and caudal with dark bars; anal 

 fin dusky ; other fins unmarked. 



We have 40 specimens of this species, ranging from 38 to 64 mm. in 

 length. These were all taken in a very muddy brackish creek at Mindi 

 near the Atlantic coast of the Canal Zone. 



The intestinal canal is short; the air bladder thin, adnate to the 

 back. The ovaries in specimens (captured on Jan. 28, 191 1) only 45 

 mm. in length are distended with well developed eggs, showing that 

 individuals of this size are mature. 



54. Microeleotris gen. nov. 



Type Microeleotris panamensis sp. nov. 



Body elongate, anteriorly depressed, caudal peduncle compressed; 

 head low and broad; eyes superior; interorbital narrow; mouth large, 

 oblique; lower jaw strongly projecting; gill-openings extending forward 

 to vertical from posterior margin of eyes; no preopercular spine; teeth 

 all small, pointed, in bands on the jaws, none on vomer; scales large, 

 ctenoid, head, chest and part of abdomen naked; dorsal fins 2, well 

 separated; caudal fin rounded; ventral fins separate, I, 5. Camiverous. 



