WHITE SHARK. 159 



aware of battles among species taking place as among 

 animals dwelling upon land, nor of struggles for su- 

 premacy during the season of amours ; but if these 

 more frequently take place in the hidden recesses 

 of the ocean, they may, with a few exceptions, be 

 carried on by the assistance of the tail and of the 

 teeth. The latter are the great predatory organs 

 among all the rapacious fishes, and the great pro- 

 portion of these continues living one on another — a 

 strong upon a weaker race. We have their struc- 

 ture in almost every variation. In the greater pro- 

 portion they are used only for seizing and securely 

 holding their prey, without assisting in any man- 

 ducatory process. In a few they crush the harder ciiis- 

 tacea and molusca before they are swallowed ; and 

 by still fewer they are placed low in the gullet, and 

 act by muscular contractions on the food as it passes 

 down, or perhaps may for a short period be retained 

 within their power. 



The shark tribe has for ages been a fruitful 

 source of terror even to man. Of these the white 

 shark ( Squalus carcharias) is the most noted. 

 His means of offence lie in the size of his mouth, 

 the strength of his jaw, the numerous teeth with 

 which his mouth is armed, and in the extreme 

 vigour and rapidity of his motions. An erroneous 

 account is usually given of the teeth of the shark : 

 it is said that the interior rows of teeth lie flat while 

 the animal is in a state of repose, and that they be- 

 come erected when it prepares to seize its prey. 

 lliG truth \% that the outer row of teeth is alone of 



