198 



Key to the species of Eleutheronema. 



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



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



I, Eleutheronema tridactylum (Blkr.) 



Folv/it'iinis ti-idaclyhis Bleeker, Nat. en Geneesk. Arch. Ned. Indie II. (3) 1845, 

 p. 524. — Verh. Bat. Gen. XXII. 1849, Bijdr. kennis Percoi'den, p. 57. 



Eleutheronema tridactyliun Bleeker, Versl. en Med. Kon. Akad. Amsterdam, 

 XIV. 1862, p. 124. 



Polynennis tridactylns Volz, Zool. Jahrb. Abth. Syst. XIX. 1903, p. 359. 



D'. VII; D^. I. 13; A.I. 15; P. i.i7+3liberi; V. 1.5; L.l. 70— 78; 

 12 

 L. tr. T. 



15 

 Elongate. Height 4 in length, 5 in length with caudal. Head }^.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 



^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]. 



