PELAGIC ANIMAL LIFE 



607 



with surface tow-nets. The beautiful Httle Hippocavipus (see Fig. 71, 

 p. 89) was taken between the Canaries and the Azores. 



The sub-order Percesoces contains several important and interesting 

 surface-fish. To the family Scombresocidae belong the gar-pike {Belone), 

 the genus Scombresox, and the flying-fish of the genus Exocoetus. 

 Sco7nbresox sauriis attains a length of 50 cm., and resembles the gar- 

 pike, but does not approach so near the coasts, nor does it extend so far 

 north ; it is known from the Atlantic coasts of North America, Northern 

 Europe and Africa. Day records a capture of icxD,ooo individuals in 

 one haul off the British shores. Only very young specimens were taken 

 by the " Michael Sars" (see Chapter X.), but these are very interesting, 

 because they prove that the species occurs pelagically right across the 

 Atlantic. Flying-fishes were constantly observed on our southern 



Fig. 464. 



datus, Giinth. Nat. size, 9. 5 cm. 



track, and some of the specimens w^hich flew on board have been 

 referred to Exocoetus spilopits. Between 40 and 50 species of this genus 

 are known from tropical and sub-tropical waters. Very interesting are 

 our captures of minute young flying-fish (see Chapter X.). The only 

 fish belonging to the sub-order Percesoces from great depths is 

 Chiasmodus niger (see Fig. 514, p. 721), taken by the "Michael Sars" in 

 the Sargasso Sea. It was previously known from the eastern and west- 

 ern sides of the Atlantic, and from the Indian Ocean. The fish has very 

 powerful teeth, and can swallow a fish much larger than itself, the diges- 

 tive tract being marvellously tensile (see Chapter X.). Lirus maculatus 

 (see Fig. 464) and L. ovalis belong to the family Stromateidae. Along 

 with Acanthopterygians, like Polyprion aviericamis, these fishes gather 

 around wreckage and other floating objects. They live in tropical 

 or sub-tropical surface waters, and biologically resemble the large lump- 

 fish or sun-fish. All the forms mentioned were captured from a boat, 

 either with a hoop-net or, in the case of Mola rotunda, with a harpoon. 



