IX . . THE SEA 355 



lures. ^ The "Sea-devil" or "Angler" of 

 our coasts has on its head three long, very 

 flexible, reddish filaments, while all round its 

 head are fringed appendages, closely resem- 

 bling fronds of sea-weed. The fish conceals 

 itself at the bottom, in the sand or among 

 sea-weed, and dangles the long filaments in 

 front of its mouth. Little fishes, taking these 

 filaments for worms, unsuspectingly approach, 

 and thus fall victims. 



Several species of. the same family live at 

 great' depths, and have very similar habits. 

 A mere red filament woiald be invisible in the 

 dark and therefore useless. They have, how- 

 ever, developed a luminous organ, a living 

 " glow-lamp," at the end of the filament, 

 which doubtless proves a very effective lure. 



In the great depths, however, fish are com- 

 paratively rare. Nor are Molluscs much more 

 abundant. Sea-urchins, Sea Slugs, and Star- 

 fish are more numerous, and on one occasion 

 20,000 specimens of an Echinus were brought 

 up at a single haul. True corals are rare, nor 

 are Hydrozoa frequent, though a gaint species, 

 allied to the little Hydra of our ponds but 



