64 BRITISH FISH AND FISHERIES. 



the trawl net, in deep water ; this net is long 

 and conical, being from sixty to seventy feet in 

 extent, with a. square mouth of eighteen feet in 

 breadth ; it is dragged along by means of a 

 rope, from a sailing-boat of ten or twelve tons 1 

 burden ; in some parts, however, the trawling 

 nets used are far larger, and the vessels are of 

 seventy or eighty tons' burden, and cutter-rigged. 



To the family of hard-cheeked fishes belongs 

 that well-known little tenant of rivers and 

 rivulets, the bull-head, or miller's thumb, 

 (Coitus golioj) common over the whole of 

 Europe, and noted for hiding itself among 

 loose stones, in the bed of the bubbling stream. 

 Two allied species, the sea scorpion (Coitus 

 scorpius) and the father-lasher, (Coitus bubalis,*) 

 with its head armed with spines, are common 

 on our coast. Here also must be placed the 

 sticklebacks, ( Gasterosteusj) of which seven spe- 

 cies are British, inhabiting lakes, brooks, ditches, 

 and the sea, around our shores. One species, 

 however, the fifteen-spined stickleback (G. spi- 

 nachia) rarely ascends rivers, and may be 

 regarded exclusively as a salt water fish. 



The sticklebacks are remarkably rapid and 

 prompt in their movements, and dart along 

 with great celerity. They feed upon insects, 

 smalj worms, and the eggs of fishes. One of 



