342 SUB-BEACHIAL SOFT-FINNED FISHES. 



alarmed, tliev do not seek to escape by flight, but 

 sink down close to the bottom and lie perfectly 

 -motionless. In the structure of the head, again, 

 there is a peculiar and very remarkable provision 

 for the wants of the creature. If the eyes were 

 placed as in all other animals, one on each side of 

 the head, it is plain that the Flat-fishes, habitually 

 grovelling in the manner described, would be de- 

 prived of the siglit of one eye, which being always 

 buried in the mud would be quite useless. To meet 

 this difficulty the skeleton is distorted, taking near 

 the head a sudden twist to one side ; and thus the 

 two eyes are placed on the side which is kept upper- 

 most, where both are available. The side furnished 

 with eyes and provided with dark colour varies in 

 the different genera ; in the Plaice, Flounder, and 

 Sole, it is the right side ; in the Turbot and Brill it 

 is the left ; while of the Holibut genus, some have 

 the right and some the left side uppermost. Indi- 

 viduals are frequently found in which the usual 

 order is reversed, and occasionally both sides are 

 coloured ; but these are casual exceptions. The 

 value of these fishes may be estimated from the fact 

 that London pays to the Dutch 80,000/. every year 

 for Turbot alone. . 



The Cyclopteri* form a small group of sub-brachian 

 fishes, distinguished by having their ventral fins 

 united so as to form a broad disk, as in 



The Lump-sucker (Cydopterus lumpus). In this remarkable 

 creature tlie pectorals and ventrals form but a single adhesive disk. 

 The skin is without scales, but covered with a thick slime, and 

 studded witli hard tubercles arranged in regular lines. Its whole 

 form is deep, thick, and short, and the first dorsal is enclosed in a 

 thick tuberculated skin. This strange-looking fish is often taken 

 upon our coasts. Notwithstanding its odd and uncouth form, it is 

 beautifully and brilliantly coloured. The back and sides are tinted 

 with deep blue, azure and purple, while the under surface and fins 

 are of a ricli orange. It is sometimes more than a foot and a half in 

 length, and almost of the same depth. Slow of motion, and incapa- 

 ble of defence, it adheres to foreign objects by means of its disk 

 so firmly that Pennant lifted a tub cont lining several gallons of 



kvk\os, cycles, a circle ; irTep6u, pteron. a fin. 



