466 



THE BEl'TUS OF THE SEA. 



[chap. ix. 



a Fusus from 1,207 fathoms was similarly provided. 

 The presence of organs of sight at these great depths 

 leaves little room to doubt that light must reach even 

 these abysses from some source. Frorn many con- 

 siderations it can scarcely be sun-light. I have 

 already thrown out the suggestion that the whole 

 of the light beyond a certain depth might be due 

 to phosphorescence, which is certainly very general, 

 particularly among the larva? and young of deep- 

 sea animals ; but the question is one of extreme 

 interest and difficulty, and will require careful in- 

 vestigation. 



BORDO, KUNO, AND EALSU, FROM J HE HAMLET OF VIDLKO. 



