PISHES. 165 



small. The head is broad, long, and depressed. The jaws are 

 capable of great distension; the upper one being "duck-biUed," 

 and the lower projecting. The mouth contains numerous 

 strong and very sharp teeth, aU pointing backwards. The 

 colour of the head and back is olive-brown. The sides are 

 lighter in shade, and are beautifully mottled with green and 

 yellow. The under-part of the body is silvery-white. The 

 dorsal, caudal, and anal fins are dark brown, the pectoral and 

 ventral fins being of a lighter brown. The former three fins 

 are blotched and spotted with dark green. Trout and Pike 

 are sxibject to a parasite {Argulus foliaceus). 



There are few fish, with the exception, perhaps, of the 

 lampem, which will give less trouble in an aquarium than 

 the Sharp-nosed or Common 

 Eel {Anguilla vulgaris) (Fig. 

 106). Its movements when 

 swimming are exceedingly 

 graceful, and its wants are 

 few and supplied without 

 difficulty. The only draw- 

 backs to its presence in an Fig. io6. Sharp-nosed Eel 

 ordinarily-arranged tank are (Anguilla vulgaris). 

 its readiness to devour, if it 



be of any size, very small fish, and a disposition to disarrange 

 a little of the sand and gravel at the bottom of the water. 



The Eel should be procured when very small — about Sin. 

 long is a suitable size for an aquarium. Eels of so short 

 a length, -however, are not often taken with a hook, and, 

 besides, an Eel caught in this way is likely to be more or 

 less injured. I have often caught Elvers (as young Eels are 

 called) by passing, during autumn, a hand-net along the 

 weedy edges of slowly-running streams. Not seldom at 

 the same haul have I secured along with Elvers, fry of perch 

 and roach. 



In the autumn, adult Eels migrate towards the mouths 

 of those livers in which they live. During this migration 

 they are supposed to spawn: very httle, however, is known 

 of their spawning. Not only do Eels migrate towards the 



