, 9 8 

 Key to the species ofEleutheronema. 



1. Three free pectoral filaments. ...... E. tridactylum p. 198. 



2. Four free pectoral filaments E. tetradactylum p. 199. 



i. Eleutheronema tridactylum (Blkr.) 



Polynemus tridactylus Bleeker, Nat. en Geneesk. Arch. Ned. Indie II. (3) 1845, 

 p. 534. _ Verb. Bat. Gen. XXII. 1849, Bijdr. kennis Percoiden, p. 57. 



Eleutheronema tridactylum Bleeker, Versl. en Med. Ron. Akad. Amsterdam, 

 XIV. lS62, p. 124. 



Polyncmus tridactylus Volz, Zool. Jahrb. Abth. Syst. XIX. 1903, p. 359. 



D 1 . VII; D 2 .I. 13; A.I. 15; P. i.i7+3liberi; V. 1.5; L.I. 70 78; 



12 



L. tr. T. 

 15 

 Elongate. Height 4 in length, 5 in length with caudal. Head 3.6, 



4.5 in length with caudal. Eyes covered by a gelatinous membrane, 

 5.3 in head, 1.6 in interorbital space, less than snout, which is 

 very prominent; the mouth beginning at a distance equal to 

 3 / 4 of the eye behind the point of the snout. Mouth very large, 

 reaching far behind eye; maxillaries scaly, 1.8 in length of 

 head. Head covered with scales to tip of snout. Anterior and 

 posterior nostrils close together, nearer to end of snout than 

 to eye. Praeoperculum serrated along its hindborder, its angle 

 produced and rounded. Neither upper nor lower lip developed, 

 excepting the lower lip near the angle of the mouth. Upper 

 and lower jaw with a broad villiform band of small teeth, 

 extending on outside of jaws. Similar teeth in a triangular 

 patch on head of vomer and in broad bands on the palatines. 

 Origin of first dorsal between that of pectorals and ventrals. 

 Origin of second dorsal slightly in advance of that of anal, 

 both fins scaly all over. First dorsal with a scaly sheath. 

 Caudal almost entirely covered with scales. First rays of 

 dorsals and anal about equal in length, less than postorbital 

 part of head. Second dorsal and anal deeply concave. Caudal 

 deeply forked. Pectorals falciform, equal to distance between 

 middle of eye and hindborder of operculum. The upper pectoral 

 filament is as long as head without snout, the second one 

 somewhat shorter and the third one much shorter. Ventrals 

 slightly longer than snout and eye. Scales finely striped, with 

 a crenulated hindborder. Colour of alcohol specimen golden, 

 darker above. Fins yellowish, pectorals somewhat darker. Length 

 354 mm. [A specimen of BLEEKER'S collection seen by us]. 



