ABDOMINAL SOFT-FINNED FISHES. 



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sight on a clear day to see them sparkling in the air, with silvery 

 brightness, or rushing from the water with an audible rustling 

 sound as tl ey spread out their large pellucid wings or fins in a 



new element, their brilliant purple backs gleaming, and their sides 

 blazing like molten metal, under the dazzling light of a tropical sun. 

 The greatest length of time they remain in the air is thirty-two 

 seconds, and their longest flight from 200 to 250 yards. 



The Siluroids differ from all other abdominal 

 Malacopterygians, in their want of true scales. 

 The skin is naked, or furnished with bony plates. 

 The dorsal and pectoral fins have a long articulated 

 spine for the first fin-ray, and there is a small adipose, 

 or soft fin, towards the hinder part of the back : one 

 species, 



The Sheat Fish (Silurus glanis), is the largest fresh-water fish in 

 Europe ; its length ordinarily exceeds six feet, and its weight is near 

 three hundred pounds. 



The Electric Silurus (Silurus electricus) of the Nile, like the 

 Torpedo and Gymnotus, possesses the power of giving strong electric 

 shocks. 



The seat of this extraordinary faculty is in a peculiar tissue, 

 situated between the muscles and the skin, and having the ap- 

 pearance of a fatty cellular structure. This fish, which inhabits the 



