140 A NATURAL HISTORY OF THE SEAS 



records, like most fish stories, are open to doubt, as was 

 evinced by the Pike represented to be 200 years old merely 

 because a Queen Anne coin was found in its interior. 

 Many fish are, however, known to live for more than 

 60 years. The shortest-lived fish is a Goby (Latrumhus), 

 which exists for but a single year. 



The air bladder is an all-important organ and like the 

 lungs of higher vertebrates is an outgrowth from the gullet. 

 In most fishes it contains a variety of gases and helps to 

 keep the fish afloat, whilst in some fresh-water forms it 

 may serve the purpose of an auxiliary breathing organ. 

 The air bladder is indeed a modified and degenerate lung, 

 which in the case of those fish which ascend the rivers 

 and invade the land has given place to the lungs, as seen 

 in the gill-bearing amphibians such as frogs, toads, newts 

 and salamanders. In the Sturgeon the inner lining of 

 the air bladder is converted into a gelatinous substance 

 known as isinglass. 



No known fish can attain to quite the size of certain 

 extinct Sharks. Those monsters are, however, almost 

 equalled in size by such a creature as the Whale Shark 

 (Rhineodon typus\ first brought to notice in 1828 and a 

 subject for wonderment and many extravagant stories 

 ever since. The smallest specimen ever taken was 14 feet 

 long, with a girth of 9! feet and the largest known measured 

 from 40 feet to 60 feet in length. An average example 

 is about 22 feet long with a mouth nearly a yard across, 

 breast fins not far short of four feet in length and a tail 

 fin nearly twice this measurement. Such proportions, 

 coupled with the Shark's jazz pattern of spots and stripes 

 make up a monster that might well strike terror to the 



