178 FISH GALLERY. 



to the sea. It occurs on ail the coasts of Europe from the 

 Mediterranean to the most northern waters of the Baltic. In 

 the Zuyder Zee and Baltic the Flounder fisheries are valuable, 

 but in Britain the annual take is only about 35,000 cwts. valued 

 at £18,000. The Flounder grows to about 3 lbs. in weight. 

 The Dab, Pleuronectes limanda, 773, is a small fish of little 

 commercial value. 



Glyptocephalus, a genus related to Pleuronectes, is represented 

 in British seas by two species, the Witch, Glyptocephalus cyno- 

 glossus, 777, and the Smear Dab, Glyptocephalus microcephaliis, 

 776. This last is often sold in the London markets as " Lemon 

 Sole," the small head and rounded outline of the body giving the 

 fish some resemblance to the true Sole. An easy test may be 

 applied by examining the scales with a lens, for the scales of 

 " Lemon Sole " are cycloid, with smooth hind edge, whereas 

 those of the Sole are ctenoid, with the exposed part rough and 

 bristly or toothed. 



The Scald-fish, Arnoglossus laterna, 778, is a small and 

 unimportant fish with a skin which is thin and tears off so 

 readily as to suggest that the fish has been scalded. Two species 

 of Topknot occur in British seas, the One-spotted Topknot, 

 Zeugopterus unimaculatus, 779, and Miller's Topknot, Zeugopterus 

 punctatus, 780 ; the One-spotted Topknot is a more southern 

 form than the other and is found as far south as the Mediterranean, 

 whereas Miller's Topknot does not occur farther south than the 

 Bay of Biscay. 



The Megrim or Whiff, Lepidorhombus megastoma, 781, is a 

 fish growing to about 18 inches in length, and occurring off the 

 coasts of Britain and Scandinavia. Ammotretis rostratus, 782, 

 and Hhombosolea jlesoides, 783, are Australian forms of Flat-fish. 

 Sole. In the genus Solea the mouth is rather small and not terminal ; 



it is curved downward towards the ventral edge. Teeth are present 

 on the lower side only. The shape of the body is oval, the 

 outline of the snout semicircular; the dorsal fin commences on 

 the snout and is not continuous with the caudal ; the lateral 

 line is straight, but with an anterior dorsal curve on the head; 

 the dorsal eye is anterior to the ventral. There are tactile filaments 



