1094 MR. G. A. BOULEXGER ON [DeC. 10, 



Pectoral 5 to | length of head, with a very short smooth spine. 

 Ventral 2 to 2:^ times as distant from root of caudal as from end 

 of snout. Uniform blackish brown, lighter brown on the belly. 



Total length 230 millim. 



Lower Niger and Old Calabar. 



5. Ohannallabes. 



Giinther, Ann. & Mag. N. H. (4) xii. 1873, p. 143 ; Boulenger, 

 Poiss. Bass. Congo, p. 263 (1901). 

 A single species. 



1. Ohannallabes apus. 



Gymncdlahes ajms Giinther, t. c. p. 142. 



Channallahes apus Boulenger, op. c. p. 264. 



Body extremely elongate and serpentiform ; length of head 

 10 to 14 times in total length. Head l^ to 1| times as long as 

 broad ; supraoecipital process acutely pointed ; a sole- shaped 

 frontal foutanelle ; an oval occipital fontanelle, partly on the 

 occipital process ; eye extremely small, nearly hidden under 

 the skin in the adult ; band of pra?niaxillary teeth 3 times 

 as long as broad ; vomei'ine teeth j^ointed, forming a crescentic 

 band which is a little narrower ; nasal barbel f to | length of 

 head ; maxillary barbel as long as head or slightly shorter ; 

 inner mandibular bai'bel a little shorter than the nasal, outer 

 mandibular a little shorter than the maxillary. Gill-rakers 

 moderately long, 9 to 10 on anterior arch. Dorsal 140-150, 

 separated from occipital process by a space equal to or greater 

 than length of head. Anal 125-130. Dorsal and anal com- 

 pletely united with 'caudal. Pectoral absent or reduced to a 

 minute rudiment without spine. No trace of ventral. Yent 

 at the antei'ior fourth of the total length. Uniform dark brown 

 or black. 



Total length 310 millim. 



Congo and Angola. 



6. Heterobranchus. 



Geofiroy, Descr. Egypte, Poiss. (1809), part; Giinther, Cat. 

 Fish, V. p. 21 (1864); Boulenger, Poiss. Bass. Congo, p. 265 

 (1901), and Fish. Nile, p. 300 (f907). 



Three species from Afi-ica, and one from the Malay Archi- 

 pelago. 



Synojysis of the S-pecies. 



D. 38-45 ; adipose fin |-f length of rayed dorsal ; pec- 

 toral not more than i length of head ; 20-30 gill- 

 raljers on anterior arch 1. S. hidorsalis I. GeofFr. 



D. 29-34 ; adipose fin as long as or a little shorter than 

 rayed dorsal ; pectoral not more than + length of 

 head; 20-30 gill-rakers on anterior arch 2. H. loiiffifilis C. & V. 



D. 30-32 ; adipose fin as long as or a little shorter than 

 rayed dorsal ; pectoral f length of head ; 18-20 gill- 

 rakers on anterior arch 3. S. isopteriis Blkr. 



