GILBERT AND STAUKS — FISHES OF PANAMA BAY 



137 



band. Upper jaw with an outer series of enlart>ed teeth, the Ixisal four-tifths of each tooth finely 

 ridged lengthwise, the terminal one-fifth abruptly smooth, separated from the ridged portion by a 

 shallow transverse groove. This structure is \ery similar to that found in Sai^enichtliys, except that 

 the terminal portion is flattened and lance-shaped in the latter, but remains conical in Paralonchurus. 

 It is interesting to note that most of the teeth are light brown in ciilor, as is usual with arrow-shaped 

 teeth. The finer teeth in Paralonchurus seem to show a similar structure to that just described. 



Pseudobranchiae are jjerfectly evident in this genus, never wholly concealed, though covered 

 by the integument. Gill-rakers very short, little movable, 6 developed on the horizontal limb of the 

 arch. Free edge of mandibular ramus with a series of delicate cilia, which are continued forward 

 along the sides of the median pore at the chin. Preopercular margin delicately denticulate, with 

 fle.xible teeth. 



Pectorals very large, t«ice as long as the ventrals, reaching the vertical from the vent, or the 

 front of the anal (in. The caudal fin is unsymmetrically lanceolate, the longest rays being those just 

 below the middle of the fin, the outline not incurved above or below these. The longest caudal rays 

 equal the longest of the pectoral fin. The outer ventral rays are produced, extending half-way to the 

 front of the anal. 



Scales all cycloid, perfectly smooth, those of the lateral line enlarged, covered with very 

 small scales. The caudal is scaled on its middle rays, the other fins wholly scaleless. 



In life, the back is grayish-brown, with light blue and bronze reflections; under parts whitish. 

 All the fins, e.xcept the spinous dorsal, are deep bright blue, appearing light brown by transmitted 

 light; the blue color persists in spirits. Posterior border of pectoral fins black; inner ventral ray 

 light brownish yellow, the outer filamentous ray whitish; anal with a narrow black margin. Branchi- 

 ostegal membranes, gular membrane and lips with some yellow. Inside of mouth and gill-cavity, 

 and lining of shoulder girdle orange-yellow. Lining of opercles jet-black, of cheeks dusky. 



Measureme7its in Hundredths of Length without Caudal. 



Length without caudal in mm 



Head 



Depth 



Eye 



Snout 



Greatest width of preorbital 



Interorbital (bone) 



Length of pectoral 



Length of third dorsal spine 



Length of longest anterior dorsal rays 



Length of third anal ray 



Length of ventrals 



Length of caudal 



Height of caudal peduncle 



