230 SALT-WATER FISHES 



in the tank within a day or two of hatching ; and Mcintosh 

 says that actually after being exposed on a microscope slide 

 in only a drop of water for over two hours the small turbot 

 recovered its vitality when restored to the tank. It is also 

 active in chasing small crustacean forms, which at that early 

 stage furnish its principal food. It has a strong preference 

 for living food, and chases its prey at the surface of the sea. 

 It is a curious fact that, although the air-bladder is absent 

 in all flat-fishes in the full-grown stage, the larval forms 

 and transitional stages possess that organ. The small turbot 

 would swim upright, like a round fish, until the meta- 

 morphosis of the eyes commenced ; but as soon as the 

 transformation begins, the fish leans over to the right side, 

 and swims henceforth with that side lowermost. 



The Megrim {Lefidorhomhus megastomd), otherwise Sail- 

 fluke, or Whiff, is a rough-scaled, thin-skinned fish ; in 

 colour, pale yellow above and sometimes showing dull 

 markings on the white side. The head, mouth, and eyes 

 are large. This flat-fish grows to a recorded length of just 

 under 2 ft., and is plentiful on the coasts of Devon and 

 Cornwall, less so on the shores of the North Sea, and 

 possibly altogether absent from the Mediterranean. This 

 very restricted range, excluding both the colder northern 

 and the warmer southern seas, is hardly in keeping with what 

 we know of the distribution of other flat-fish, and Cunningham 

 offers a more likely explanation on the ground that in all 

 probability the megrim keeps on certain coasts outside of the 

 limit usually worked by trawlers, and may thus escape notice. 

 Whether the results of the deep-water hauls during the Irish 

 survey were in themselves sufficient to warrant such a theory 

 is not clearly stated ; but this view bears on it the imprint 

 of probability. 



Like the brill and turbot, the species under notice feeds 

 almost entirely on small fishes, particularly sand-eels. 



The spawning, at any rate, appears confined to deep water, 



