107(5 ME. G. A. BOULENGER ON [DeC. 10, 



3-1- to 34 times. Head 1| to 1| times as long as broad, perfectly 

 smooth above ; vertex very strongly flattened, almost concave in 

 the adult ; occipitaj process angular ; frontal f ontanelle knife- 

 shaped, 3 to 4 times as long as broad, 4 to 5 times in length 

 of head ; occipital f ontanelle indistinct ; eye 2| (young) to 4 

 times in length of snout, 4 to 6|- times in interorbital width; 

 width of mouth nearly equal to interorbital width ; band of prae- 

 maxillary teeth 4 to 5| times as long as broad ; vomerine teeth 

 granular, forming a crescentic band which is as broad as the 

 prsemaxillary band ; nasal barbel ^ to g length of head (| in the 

 very young) ; maxillary barbel | to once length of head (longer 

 in the very young), reaching base or extremity of pectoral spine ; 

 outer mandibular barbels ■!■ to 4 length of head (as long as head 

 in the very young). Gill-rakers long and closely set, 45 (young) 

 to 70 on anterior arch. Dorsal 78 to 85, its distance from the 

 occipital process 1- to | length of head, its distance from caudal 

 fin equal to or a little less than diameter of eye. Anal 60 to 70, 

 touching root of caudal. Pectoral not quite half length of head, 

 the spine very slightly serrated on the outer border, |- (young) to 

 -| the length of the fin. Ventral equally distant from end of 

 snout and from caudal, or a little nearer the former. Caudal 

 nearly ^ length of the head. Dark olive-brown above, greyish 

 beneath. 



Total length 430 millim. 



Lake Tsana, Abyssinia. 



10. Olarias capensis. 



Cuvier & Valenciennes, Hist. Poiss. xv. p. 377 (1840); 

 Boulenger, Poiss. Bass. Congo, p. 255 (1901). 



Depth of body 6|- to 7^ times in the total length, length of head 

 4 times. Head once and ^ as long as broad, its upper surface 

 coarsely granulate ; occij)ital process angular ; frontal fontanelle 

 3| to nearly 4 times as long as broad, 4 to 5 length of head ; 

 occipital fontanelle very small, well in advance of occipital process ; 

 eye very small, its diameter 3-4 times in length of snout, 5-7 

 times in interorbital width, which equals width of mouth and 

 |- length of head ; band of prsemaxillary teeth 6 times as long as 

 broad ; band of vomerine teeth a little narrower than the prse- 

 maxillary band, rather widely interrupted in the middle, com- 

 posed of small, partly pointed, partly granular teeth ; nasal barbel 

 ^ to neai'ly i length of head ; maxillary barbel as long as head, 

 reaching middle of pectoral spine ; oviter mandibular barbel 

 f length of head, inner about g. Gill-rakers on first arch long 

 and closely set, 55 in number. Clavicles hidden under the skin. 

 Dorsal fin with 63-72 rays, its distance from occipital process y 

 to 5 length of head, its distance from caudal 1-4 times diameter 

 of eye. Anal fin with 50-52 rays, narrowly separated from 

 caudal. Pectoral fin 4 length of head, the spine feebly serrated 

 on the outer border, |— 4 the length of the fin. Ventral fin once 



