Dec. 28, 1916. FisHes of PANAMA— MEEK AND HILDEBRAND. 363 
KEY TO THE SPECIES. 
a. Scales in lateral series 33 to 36; second dorsal with I, 8 rays; anal 
I, 8. panamensis sp. nov., p. 363. 
aa. Scalesin lateral series 30 to 32; second dorsal with I, 9 rays; anal I, 9. 
mindit sp. nov., p. 364. 
89. Microeleotris panamensis sp. nov. 
Type No. 8953, F. M. N. H.; length 50 mm.; Rio Juan Diaz, 
Panama. 
Head 3.25 to 3.6; depth 4.75 to 5.5; D. VI-I, 8; A. I, 8; scales 33 to 36. 
Body anteriorly depressed; caudal peduncle compressed; head de- 
pressed, notably wider than deep, its width at preopercular margin 1.25 
to 1.42 in its length; the upper profile slightly convex; snout tapering, 
its length 3.4 to 4 in head; eye rather small, superior, 4 to 5.64; inter- 
orbital narrow, 5.5 to 7.25 in head; mouth rather large, oblique; the 
lower jaw strongly projecting; maxillary scarcely reaching middle of 
eye, 2.04 to 2.8 in head; teeth all small, pointed, in bands in the jaws; 
gill-membranes rather narrowly attached to the isthmus, the openings 
extending forward to vertical from posterior margin of eye; scales large, 
ctenoid, none on head, chest and abdomen, 7 or 8 rows between base of 
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 short and weak, 
reaching second dorsal when deflexed; origin of second dorsal slightly in 
advance of origin of anal, the rays short; caudal fin not scaly at base, its 
margin evenly convex; anal fin similar to second dorsal; ventral fins 
short, failing to reach vent, inserted under base of pectorals; pectoral 
fins moderate, 1.18 to 1.4 in head. 
Color grayish brown above, pale below. Body above and on sides 
spotted and marbled with dark markings; back sometimes with a few 
dark saddle-like bars; sides often with quadrate blotches; a more or less 
distinct caudal spot present. Dorsals, caudal, and usually the pectorals 
spotted and barred with dark markings; anal and ventrals pale or dusky. 
This species is represented by 38 specimens, ranging from 30 to 58 
mm. in length. These were taken in fresh water, not far above the head 
of tide, in the Rio Chorrera near Chorrera and in the Rio Juan Diaz at 
Juan Diaz on the Pacific slope. 
The intestinal canal is short. The stomachs examined contained 
small molluscs, principally snails. The ovaries in two specimens, each 
about 45 mm. in length, taken on April 4, rgrz, were distended with 
well developed eggs, showing that fish of this size are mature. 
A specimen 50 mm. in length from the Rio Juan Diaz has been 
designated as the type. 
Habitat: Pacific slope of Central Panama. 
