THE PROBLEM OF PAIN IN FISHES ir,l 



defined by pigment, as in the haddock. These organs are very 

 similar to the sense orgaiLs in the ain])unae of the semi-circular 

 canals of the fish's ear and their function is to register waves of low 

 frequency. 



Finally we come to an organ peculiar to fish, the function of 

 ^^•hich has been investigated recently by Dr. Sands at the Plymouth 

 ^Marine Laboratory ; by means of an oscillograph he has made 

 tracings of the action currents in these mucus canals, named from 

 their discoverer, Lorenzini's ampullae, and finds that they record 

 changes of temperature. To review the functions of the epidermis 

 of fish we find Touch, Chemical Sense, Taste, Vibrations and Tem- 

 perature all represented ; we have no means of recognising pain- 

 spots, but we may assume their existence as they are a primitive 

 form, and even if they do not exist we have seen that excessive 

 stimulation of any sense organ can produce a painful sensation. 



There is one more piece of evidence pointing to the perception 

 of 25ain in fish. IMany fish are provided with poisonous spines, and 

 the most marked effect of the puncture by these spines is acnte 

 pain, in man of an excruciating nature : these organs were not 

 evolved for protection against man. Fish have been seen to attack 

 small fry with these spines, and experimental observations show 

 that acute symptoms follow the subcutaneous injection of the 

 venom of these organs. In conclusion we may say that there is 

 no evidence that fish do not feel pain, and there is no reason to 

 suppose that they are devoid oi' a protective mechanism common 

 to most vertebrates. 



