FINNY LIGHT-BEAREES. 93 



some forms must attract their enemies ; while, on the other 

 hand, they may constitute a lure, dazzling weaker forms, 

 which fall victims to their curiosity. 



Among all the light-givers, these deep-sea lantern-bearers 

 are the most interesting, and typical of the mysterious realm 

 from which they are taken by the ingenious inventions of 

 mankind. Some are luminous over their entire surface, as 

 the Harpodon, or Bombay duck (Plate XVIII., Fig. 2). 

 Others have a series of plates extending along the side, that 

 resemble the open ports of a steamer. Some possess gleam- 

 ing head-lights, the locomotives of the sea ; while others have 

 their lights confined in groups. 



While the expeditions of the " Challenger," " Talisman," 

 " Albatross," and " Travailleur " have resulted in the dis- 

 covery of what seems a remarkable presentation of these 

 light-givers, we can well imagine, understanding the diffi- 

 culties of deep-sea dredging, that the largest and perhaps 

 most interesting of these forms are yet undiscovered, and 

 that the greatest mysteries may never be revealed. The 

 difficulties that attend, and the chances against, the capture 

 of deep-sea fishes, can be perhaps realized by my young 

 readers, if they imagine a large balloon sailing along over 

 the country at an elevation of from four to five miles, drag- 

 ging a dredge ten or twelve feet wide. Few active boys 

 or girls would be caught by such a device ; only the slug- 

 gards that were fast asleep would be trapped. The com- 

 paratively small dredge at the end of a six-mile rope, dragging 

 along and creating an unusual commotion in the silent sub- 

 marine world, secures only a few forms, the sluggards and 

 mud-lovers, as a rule : so that fishes taken at extreme depths 

 are prizes indeed. The " Talisman " took the fish Bythites 



