254 THE HARMONIES OP NATURE. 



newest layers of the stony corals, digesting the animal matter 

 therein contained, and setting free the carbonate of lime in a 

 chalky state. 



The maxillary teeth of the sawfish, which is an active and 

 predatory shark, are notwithstanding its habits extremely 

 small, simple, obtuse, and wholly inadequate to destroy and 

 secure the prey requisite for its subsistence. But this seemingly 

 imperfect armature of the mouth is compensated by the de- 

 velopment from the anterior part of the head of a horizon- 

 tally flattened process, equalling one-third of the entire fish in 

 length, and provided with strong teeth, 

 deeply lodged in sockets excavated on 

 each of its lateral margins. With this 

 formidable weapon, which is quite unique 

 among the whole finny race, the sawfish 

 does not fear to engage even the monstrous 

 whale in deadly combat. The whale, 

 whose only defence is his tail, endeavours 

 to strike his enemy with it ; and a single 

 blow would prove mortal. But the saw- 

 fish with astonishing agility shuns the 

 tremendous stroke, bounds into the air, 

 and returns upon his huge adversary, 

 plunging the rugged weapon with which 

 he is furnished into his back, or ripping 

 up his skin with a tremendous gash. The 

 whale is still more irritated by the wound, 

 which becomes fatal only when it pene- 

 trates the fat ; and thus, pursuing and 

 pursued, striking and stabbing, the en- 

 gagement only ends with the death of 

 one of the unwieldy combatants. 

 Rostrum of Sawfish While most fishes rely only upon their 



(Pristis antiquonirQj, show- 



mg the marginal teeth, teeth, their physical strength, or their 

 rapidity for attack or defence, some have been gifted with the 

 wonderful power of stunning their enemies or their victims by 

 electrical discharge. In no other class of animals do we find 

 creatures similarly armed; and it is indeed one of the inscrutable 

 mysteries of creation, that the powerful weapon of a galvanic 

 battery, which man lias, learned to wield only after attaining 



