PILOT-FISH. 



365 



s edible. The genus is represented in the Monte Bolca Eocene. Horse-mackerel 

 ometimes make their appearance in enormous shoals on the British coasts ; and it 

 s stated that on one occasion upwards of ten thousand were taken in Cornwall. 

 A. correspondent of Yarrell wrote, that in the summer of 1834 vast shoals of these 

 fish were seen on the Glamorganshire coast. " They were first observed in the 

 vening, and the whole sea, as far as we could command it with the eye, seemed in 

 state of fermentation with their numbers. Those who stood on some projecting 

 ock had only to dip their hands into the water, and with a sudden jerk they 

 might throw up three or four. The bathers felt them come against their bodies, 

 nd the sea, looked on from above, appeared one dark mass of fish. Every net was 

 mmediately put in requisition ; and those which did not give way from the weight, 

 were drawn on shore laden with spoil. One of the party who had a herring-seine 

 vith a two-inch mesh was the most successful ; every mesh held its fish, and 

 'ormed a wall that swept on the beach all before it. The quantity is very iriade- 



PILOT-FISH. 



Pilot-FisH. 



uately expressed by numbers, they were caught by cart-loads. As these shoals 

 vere passing us for a week, with their heads directed up channel, we had the 

 pportunity of noticing that the feeding-time was morning and evening. They were 

 mrsuing the fry of the herring, and I found their stomachs constantly full of them." 

 Another genus is represented by the pelagic pilot-fish (Naucrates 

 ductor), which takes its name from a supposed habit of guiding and 

 >ro tec ting the sharks and ships which it accompanies. Having no plates on the 

 ateral line, this fish is further characterised by the rounded under surface of the 

 )ody, by the first dorsal fin being composed in the adult of detached spines, by the 

 bsence of finlets, and the presence of a keel on each side of the tail. When adult, 

 be pilot-fish measures about a foot in length. In colour it is bluish, with five or six 

 ark vertical bands ; the tail-fin sometimes having the ends of its two lobes dark, 

 s also a band across the middle third. Ranging over all temperate and tropical 

 eas, pilot-fish were regarded as sacred by the ancients, by whom they were known 

 s pompili ; the common belief being that when the ship neared land, the fish 

 uddenly disappeared, and thus gave warning to the sailors of impending danger. 

 Many legends have grown in later times as to how pilot-fish will prevent sharks 



