TIGERS OF THE DEEP 



The thornback is a common ray in the coastal waters 

 of Great Britain, and is taken plentifully along our shores. 

 It is so called from the number of thorny projections 

 scattered over its back and along its spine. 



Known also by the sinister name of devil-fishes, the 

 eagle rays include some of the largest representatives of 

 their tribe, and are characterized by their flatness and 

 extreme width. The tail is slender and whip-like, the 

 mouth-cleft straight, and the teeth, when present, form 

 a mosaic or pavement, perfectly adapted for crushing the 

 shells of molluscs and other hard substances. The teeth 

 are arranged in seven longitudinal rows, those of the 

 unpaired middle row being much elongated, while the 

 other rows form irregular hexagons. Some of the fossils of 

 this genus show that the living creatures of prehistoric 

 times must have had tusks five inches in length. Our 

 modern ones may attain a length of ten feet and weigh 

 several hundredweights. When captured these eagle rays 

 lash out fiercely with their tails, the spines of which may 

 inflict considerable damage. 



But there are even bigger devil-fishes. The largest 

 existing members of the family belong to the genera 

 Dicerobatis and Cephaloptera, and are mainly confined to 

 the tropical seas. In the former the pectoral fins do not 

 extend to the sides of the head, which is cut away in 

 front and furnished with a pair of appendages which are 

 directed forward, Hke horns, the nostrils being widely 

 separated, so that the creature's appearance is certainly 

 devilish. One of the Indian representatives of this genus 

 is known to measure eighteen feet across its disc, while a 

 weight of 1,200 pounds — over half a ton — has been 

 recorded. Sir W. Eliot, who gave special study to this 

 fish, stated that the horn-hke appendages "are used by the 

 animal to draw its prey into its mouth, which opens like 

 a huge cavern between them. The fishermen in India 

 say they see these creatures swimming slowly along with 

 their mouths open, and flapping these great sails (the 



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