282 



ADDENDA, VOL. IT. 



7 a. OLARIAS NGAMENSIS. 



Casteln. Mem. Poiss. Afr. Austr. p. 63 (1861) ; Bouleng. Tr. Zool. Soc. xviii. 1911, 

 p. 404, pi. xxxviii. fig. 2 ; Gilclir. & Thouips. Ann. S. Afr. Mus. xi. 1913, 

 p. 443. 



Depth of body 6§ times in total length, length of head 3 times. 

 Head If times as long as broad, smooth above (young); occipital 

 process angular ; frontal fontanelle 3- length of head; occipital fontanelle 

 small, in advance of occipital process ; eye 3 times in length of snout, 

 5 times in interorbital width, which equals width of mouth and f length 



Fig. 173. 



Clarias ngamensis. 

 Okovango E. (Tr. Z. S. 1911). \. 



of head ; band of prsemaxillary teeth 4 times as long as broad ; vomerine 

 teeth granular, forming a crescentic band which, in the middle, is 

 nearly twice as broad as the prsemaxillary band ; anterior mandibular 

 teeth pointed, posterior granular. Nasal barbel \ length of head, 

 maxillary f, reaching middle of pectoral spine, outer mandibular f, 

 inner mandibular \. Gill-rakers long, about 30 on anterior arch. 

 Clavicles striated, distinct under the thin skin. Dorsal 60, its distance 

 from occipital process \ length of head, its distance from caudal 

 fin \. Anal 50, narrowly separated from caudal. Pectoral not quite 

 \ length of head, its spine serrated on the outer border and § the 

 length of the fin. Ventral equally distant from end of snout and 



