OSSEOUS FISHES. 
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worms, on which it feeds, while it shelters itself from the jaws of 
many voracious fishes, which eagerly pursue it for its delicate flesh. 
In appearance the Ammodytes lancea is silvery blue, brighter on the 
lower parts than on the upper, the radiating fins on the abdomen 
being alternately white and bluish in colour. 
Fig. 362 . Thb Lance ( A. lancea).' 
The Gymnotes are long, nearly cylindrical, and also serpent-like, 
the tail being long in comparison to the other parts of the body. 
Beneath the tail is a long swimming fin, the only locomotive organ, 
Fig. 36 The Gymnotus Elect ricus, or Electrical EeL 
a nd it is this nakedness of the back which confers its designation of 
yv/ivos, naked, vo>to ?, back. 
The Gymnotes are fresh-water fishes of South America, where they 
attain a great size. There are several species ; but the most remark- 
