RIVEB BULLHEAD. 59 



fish possesses the property of indicating, by the direction of 

 the head, the point of the compass from which the wind 

 blows. In Switzerland the children spear them in shallow 

 water as they move from the stones under which they hide. 

 Cuvier recommends this fish as a favourite bait for an eel. 



D 6to9— 17or 18 : P. 15 : V. 3 : A. 13 : C 11. 



The size and form of the head has been already noticed : 

 the mouth is wide, jaws nearly equal, numerous small sharp 

 teeth in both jaws and on the anterior part of the vomer ; no 

 spines on the head ; irides yellow, pupils dark blue ; preoper- 

 culum with one spine curved upwards ; the operculum 

 ending in a flattened point ; the dorsal fins united by 

 a membrane ; rays of all the fins prettily spotted ; general 

 colour of the body above dark brownish black, sides lighter, 

 with small black spots ; under surface of the head and belly 

 white ; the vent in a vertical line under the commencement 

 of the second dorsal fin. This species spawns in summer. 



