OPHIOCEPHALUS. 437 



OPHIOCEPHALID^E. 



Mouth protractile, the maxillaries excluded from the oral border. Body covered 

 with cycloid or feebly ctenoid scales. Anterior ribs sessile, the remainder inserted on 

 the parapophyses ; epipleurals on the anterior ribs. Pectoral fin low down ; ventral fin, 

 if present, near the pectoral, with six soft rays ; pelvic bones connected with the 

 clavicular symphysis by ligament. Dorsal and anal fins long, without spines. 

 Air-bladder present, much elongate, bifid behind and extending far into the caudal 

 region. • 



Carnivorous fishes provided with an accessory superbranchial cavity, through which 

 they are able to breathe atmospheric air. All are inhabitants of fresh waters. 



The Ophiocephalidse resemble the Mugilidae in the form of the head, nearly entirely 

 covered with scales, which are largest above and suggest the head-shields of snakes, 

 whence the name Ophiocephcdus. The branchiostegal rays are 6 in number; 

 pseudobranchige are absent. 



The range of this family extends over Tropical Africa, Southern Asia, and China. 

 Only two genera are distinguished : Ophiocephalus and Channa. 



1. OPHIOCEPHALUS. 



Blocli, Nat. Ausl. Fische, vii. p. 137 (1793) ; Giinther, Cat. Fish. iii. p. 468 (1861) ; 

 Boulenger, Poiss. Bass. Congo, p. 367 (1901). 



Body elongate, cylindrical or a little depressed in front, covered with small or 

 moderately large scales ; lateral line complete, sometimes interrupted. Head depressed, 

 flat and covered with large scales above ; mouth large, with bands of cardiform 

 teeth, often intermixed with enlarged, canine-like teeth in the lower jaw; teeth 

 on the vomer and palatines. Anterior nostril in a tentacle-like tube. Gill-openings 

 large, the gill-membranes attached to the isthmus ; an accessory cavity, without 

 superbranchial organ, above the gill-chamber. Dorsal and anal fins much elongate ; 

 ventral fins present. Vertebrae 39 to 61. 



This genus includes about 30 species, mostly from China and South-eastern Asia. 

 Three species are known from Tropical Africa, one of which occurs in the 

 White Nile and the Bahr-el-Gebel. 



