Descriptions of Fishes from the Coast of Natal. 93 



FAMILY GYMNODONTES. 



GEN. TETEODON, L. 



TETRODON IMMACULATUS, Bl. Schn. 

 Syst. Ichth., p. 507, 1801. 



Teeth equal on both jaws. Length of head nearly equals its 

 distance from dorsal fin and is 2^ times in the total length exclud- 

 ing caudal. Eyes comparatively small, situated high up and about 

 midway between gill-opening and end of snout, and 3f times in 

 length of snout, which is slightly more than \ length of head ; inter- 

 orbital space flat, its width slightly less than length of snout, the 

 osseous part about 3 times diameter of eye in width ; 2 solid nasal 

 papillae on each side of an impervious nasal fossa. 



Dorsal 11 ; situated in posterior third of distance from snout to 

 base of caudal fin, length of base of fin equals \ its height, anterior 

 rays longest and \ length of head. Pectorals 18 ; a little more than 

 ^ length of head. Anal 11 ; situated midway between posterior 

 margin of dorsal fin and base of caudal, of similar shape to dorsal 

 fin but smaller. Caudal truncated, \ length of body. Spines cover 

 the whole body except the snout and the caudal peduncle, strongest 

 and most numerous on the belly. 



Colour (of preserved specimen), olive-brown on back, shading 

 to light brown on sides, belly white ; pectorals straw-colour, situated 

 in the middle of a large round black spot which also extends on 

 to their base and covers the gill-openings ; anus in a black ring. 



One specimen, 310 mm. in length, from Mr. Eomer Eobinson, 

 Natal. 



