THE POISON OF THE MURRY 



selves and are almost as much dreaded. Yet they 

 only display, in an exaggerated degree, a quality which 

 is possessed by most fishes, if not by all. Fishermen 

 know that our fresh-water species, even the most 

 ordinary of them, can sometimes cause painful and 

 cruel wounds, if one happens to prick oneself on a fin 

 or spur on the gill-cover. It does not always happen, 

 but it happens often enough to show that there is a 

 general cause, usually benign, but capable of being 

 accentuated and intensified in certain species in certain 

 circumstances or at certain times. 



This cause arises from the accustomed condition 

 of fishes. In many of them, the skin is covered with 

 a slimy mucus which, attaching itself to the scales, 

 covers the body with a protecting coat. This mucus 

 contains in varying proportions certain toxic products 

 excreted by the teguments. These products inoculated 

 in a chance wound may set up inflammation. Some- 

 times accumulating in certain areas in greater quantity, 

 they become associated with spines, and form a sort 

 of poisonous apparatus. 



This apparatus, however, serves only as a defence 

 in case of emergency; it is a momentary means of 

 self-preservation. The sting-rays when they He buried 

 in the sand bed, the hog-fish in their hollows among 

 the rocks beneath the foliage of seaweed and grass- 

 wrack, never use these poisonous stings to attack their 

 neighbours, and not even to defend themselves against 

 them. Their life usually is passed as if they did not 

 possess such an armament, like that of fishes not so 

 equipped. I see them in their tanks, looking like 

 any other fish, showing no peculiar mode of behaviour. 

 They possess such an organ, but as a secondary 

 characteristic, often quite inoperative. 



This is not exactly the case with the murry. The 



poisonous organ is in another place, the mouth, and 



for that very reason its quality is accentuated. Although, 



in the ordinary course of events, the creature does not 



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