496 SILUKID.E. 



34. DOUMEA. 



Sauvage, Bull. Soc. Fhilom. (7) iii. 1878, p. 96, and N. Arch. Mus. (2) iii. 1880, 

 p. 41 ; Bouleng. Ann. & Mag. N. H. (7) vi. 1900, p. 526. 



Body elongate, feebly depressed, with extremely slender caudal 

 peduncle. Two short dorsal fins, the anterior entirely in advance of the 

 ventrals and formed of one simple, thickened but articulated, and 6 

 branched rays, the second much smaller, opposed to the anal, and formed 

 of fine rays partly concealed in adipose tissue ; pectoral and ventral fins 

 large, horizontally expanded, the outer ray much thickened but not 

 ossified, formed of very numerous articles angularly bent and produced 

 on the outer side into a fringe imbedded in the thickened integument; 

 ventral with 6 rays. No cephalo-nuchal shield. A maxillary and two 

 mandibular barbels on each side, verrucose like the lips. Nostrils 

 remote from each other, both with a valve. Eye small, without free 

 border. Mouth small, inferior, surrounded with thick papillose lips ; 

 small pointed prsemaxillary teeth ; mandibular teeth few or absent ; 

 palate toothless. Gill-openings narrowly interrupted at the isthmus, the 

 membrane forming an uninterrupted transverse fold. Air-bladder absent. 



Vertebrae 37 (17 + 20). 6 branchiostegal rays. 



Cameroon to Angola. 



Two species : — 



Head If to 1^ times as long as broad, snout 1| 



to 1^- times as long as postocular part of 



head ; space between the two nostrils on 



each side equally distant from end of snout 



and from eye 1. D. typka, Sauv., p. 496. 



Head 1\ times as long as broad, snout 1^ times 



postocular part of head ; posterior nostril 



nearer eye 2. D. angolensis, Blgr., p. 497. 



1. DOUMEA TYPICA. 

 Sauv. 11. cc. pi. iii. fig. 1 ; Bouleng. t. c. p. 527, and xii. 1903. p. 440. 



Depth of body slightly less than its width, 1\ to 9 times in total 

 length. Head strongly depressed, with slightly rugose vertex and 

 occiput, covered with a thin skin, If to \\ times as long as broad, 5 to 

 5| times in total length ; snout pointed, projecting a little beyond 

 mouth, 1 1 to If times as long as postorbital part of head ; space between 

 the two nostrils on each side equally distant from end of snout and from 



