266 MARKETABLE BRITISH MARINE FISHES 



horizontal, in the same position, or nearly, as when lying on 

 the bottom. 



The advantage of this power and habit of swimming at the 

 surface is not difficult to discover. Even at these early stages 

 the turbot and brill are rapacious and feed on other fishes smaller 

 than themselves. They might capture such prey when lying 

 like the adult at the bottom, but in summer time the young of 

 other kinds of fishes are much more plentiful in the open water 

 and near the surface than at the bottom. In the aquarium at 

 Plymouth the young turbot have been fed on pieces of dead fish, 

 but both they and the brill much prefer living prey, and when 

 kept with other young fish, such as flounders, speedily devour 

 them, or choke themselves in the attempt. 



After completing their transformation, losing the air-bladder, 

 and assuming the habits of the adult fish, young turbot have 

 only been found in very shallow water, near the margin of the 

 sea. At St. Andrews they have been taken with a seine net in 

 September and October, at a length of 2 inches. These are 

 doubtless the young hatched the previous summer. At Clee- 

 thorpes, from April to June, specimens from 3 inches to 4^ 

 inches long are taken in small numbers in the shove-nets of the 

 shrimpers. These are only the smallest of the brood of the 

 preceding year, the majority of turbot a year old being larger. 

 The limiting sizes of mature and immature turbot observed at 

 Grimsby were for females 14 inches and 19 inches, for males 

 12 inches and 15 inches. As in other cases, these limits give the 

 sizes attained by some specimens at two years of age, while the 

 size of the smallest mature male may be taken as the greatest 

 size reached by the female at the end of the first year. On the 

 eastern grounds of the North Sea small turbot are taken in 

 considerable numbers, together usually with a proportion of 

 adults. The total catch on one voyage of a steam trawler on 

 these grounds in June w r as 140 specimens, ranging in size from 

 II to 15 inches. Judging from the size, some of these may have 

 been mature. In a single haul of the trawl at 10 to 12 fathoms, 

 about twenty miles from the Amrum Light, north of Heligoland, 

 also in June, there were taken two mature female turbots 14^ 

 inches and 24 inches long, nine immature females 13^ inches to 

 15^ inches, and twelve mature males 13 inches to 16 inches. 

 There can be no doubt that the year-old turbot, mostly from 



