234 INTRODUCTION TO ZOOLOGY. 



Arabs give a name signifying thunder.* Another is the 

 Torpedo or Electric Ray of our own shores (Fig. 191); and 

 a third is the Gymnotus or Electric Eel of 

 the South American rivers, whose shock is 

 sufficiently powerful to stun and even destroy 

 horses. Humholdt gives a most graphic 

 picture of the scene attending their capture; 

 the livid yellow Eels swimming near the 

 surface and pursuing their enemies, the groups 

 of Indians surrounding the pond, and the 

 horses with their manes erect and eyeballs 

 wild with pain and fright, striving to escape 

 from the electric storm which they had 

 roused, and driven back by the shouts and 

 Fig. 191 TORPEDO, long whips of the excited Indians. 



VITALITY. There are some fishes which die almost imme- 

 diately when taken out of the water, and others which exhibit 

 symptoms of life after a lapse of several hours. In reference 

 to this subject Mr. Yarrell remarks " that those fish that swim 

 near the surface of the water have a high standard of 

 respiration, a low degree of muscular irritability, great necessity 

 for oxygen, die soon almost immediately when taken out 

 of the water, and have flesh prone to rapid decomposition. 

 On the contrary, those fish that live near the bottom of the 

 water have a low standard of respiration, a high degree of 

 muscular irritability, and less necessity for oxygen; they 

 sustain life long after they are taken out of the water, and 

 their flesh remains good for several days."t The phenomena 

 connected with this law are highly interesting, and excite the 

 attention of the most incurious. Mackerel are so perishable 

 that they are permitted to be cried through London for sale 

 upon the Sunday. Herrings die so instantaneously on their 

 removal from the water, that the saying "dead as a herring," 

 has become proverbial. Perch, on the contrary, live for some 

 hours: " They are constantly exhibited in the markets of 

 Catholic countries, and, if not sold, are taken back to the 

 ponds from which they were removed in the morning, to be 

 reproduced another day." j The Anglesey Morris, a small 

 fish of rare occurrence, has been known to survive after being 



* Milne Edwards' "Elemens," p. 281. 

 Yarrell, vol. i. p. 3. 

 Idem, vol. i. p. 22. 



