622 THE LIVING ANIMALS OF THE WORLD 



descried, all that remains to be done is to seize hold of it and drag it ashore, if it has not 

 already stranded itself, and then dispatch it. 



The Barracuda, or Snuek, is likewise a New Zealand species, attaining a length of 5 feet. 

 It is found also at the Cape and South Australia. In New Zealand the flesh is exported to 

 Mauritius and Bataxia as a regular article of commerce, being worth £i'j per ton. 



The HoRSE-ALVc'KERELS, or SCADS, are represented by some very bizarre-looking forms. It 

 is a large famil}-, belonging to tropical and temperate seas. One species, the COMMON HORSE- 



Photoi by IV. Saville-Kinl, F.Z.S.'j 



iMilfaril-on-Su 



JOHN DORIES 



T/ieie fwo plioto^taphs sho'W the difference in t/ie ja-zus ivhen protruded and ivhen at reit 



MACKEREL, is common in British seas. Many members of the family have the hinder portion 

 of the body on each side armed with large plates, well seen in the accompanying 

 photographs; others ha\'e the median fins produced into long filamentous processes. All are 

 eatable, and some highl)' esteemed as food. One of the most remarkable is the PlLOT-FlSH of 

 tropical and temperate seas, occurring occasionally off the British coasts. It derives its name 

 from its habit of accompan)'ing ships and large sharks. From this habit of accompanying 

 ships it was regarded b)- the ancients as a sacred fish, since they considered it pointed out 

 the way to embarrassed sailors, and announced the vicinity of land by suddenly disappearing. 

 The close companionship between the pilot-fish and the shark has excited much comment, 

 many observers believing that the former was of great use to the latter in guiding it to its 

 food. How this is done is graphically described by Dr. Me\-er, who writes: " The pilot swims 

 constantly in front of the shark; we ourselves have seen three instances in which the shark 

 was led b)' the pilot. When the shark neared the ship, the pilot swam close to the snout or 

 near one of the pectoral fins of the animal. Sometimes he d.u'ted rapidly forwards or sidewards, 

 as if looking for something, and c(.)nstantly went back agai.i to the shark. When we threw 

 overboard a piece of bacon fastened on a great hook, the Uiark was about twenty paces from 

 the ship; with the quickness of lightning the pilot cane up, smelt at the dainty, and 

 instantly swam back again to the shark, swimming many times round his snout and splashing, 

 as if to give him exact information as to the bacon. Tne shark now began to put himself 

 in motion, the pilot showing him the way, and in a moment he was fast upon the hook." 

 As Dr. Gunther remarks, commenting on this account, one may entertain reasonable doubts as 

 to the usefiilncss of the pilot to the shark in this instance! It is probable that the pilots 

 follow the sharks for the sake of feeding on fragments scattered by the latter, and also for 

 the sake of picking off the parasites with which sharks, in common with other large fish, are 

 infested; fiirthermore, the pilot, being but a small fish, obtains greater security from enemies 

 when in the company of its giant friend. The habit of seeking the company of more 

 powerfiil or otherwise offensive animals is apparent also in other members of this family, the 



