326 



THE SEA SHORE 



to, and apparently live perpetually in, perfectly fresh water. In 

 many instances they may be seen miles from the sea, and even 

 flourishing in little fresh-water streams only a few feet in width. 

 Thus they may be found in numbers in the upper waters of the small 

 rivers of the Isle of Wight and of many streams of the mainland. 



The principal British flat-fishes are the Plaice (Pleuronectes 

 platessa) and Flounder (P.flexus) above mentioned, and also the 

 Sole (Solea vulgaris), the Lemon Sole (S. aurantiaca), the Turbot 

 (Rhombus maximus), and the Halibut (Hippoglossus vulgaris) ; 

 and as all these are well-known food-fishes it is hardly necessary to 

 describe them. 



Sand Eels (family OpTiidiidce) resemble the true eels in the 



FIG. 233. THE LESSER SAND EEL 



general form of their elongated bodies, but may be readily distin- 

 guished by their bright silvery colour, the large gill-openings, and 

 the more strongly developed dorsal and ventral fins, the former of 

 which extends almost along the whole length of the back. The 

 lower jaw is also longer than the upper. 



Two species are to be found on our shores the Lesser Sand Eel 

 (Ammodytes tobianus), and the Greater Sand Eel (A. lanceolatus), 

 the former attaining a length of six or seven inches, and the latter 

 nearly three times this size. They may be seen off the south coast, 

 swimming in shoals over sandy bottoms, and when disturbed they 

 descend and burrow into the sand with remarkable agility. They 

 approach the shore so closely that they are often washed up by the 



