IX THE SEA 351 



denly appear globes of soft and lambent light, 

 given out perhaps from the surface of some 

 large Medusa. 



" A beautiful white cloud of foam," says 

 Coleridge, " at momently intervals coursed by 

 the side of the vessel with a roar, and little 

 stars of flame danced and sparkled and went 

 out in it ; and every now and then light de- 

 tachments of this white cloud-like foam darted 

 off from the vessel's side, each with its own 

 small constellation, over the sea, and scoured 

 out of sight like a Tartar troop over a wilder- 

 ness." 



Fish also are sometimes luminous. The 

 Sun-fish has been seen to glow like a white- 

 hot cannon-ball, and in one species of Shark 

 (Squalus fulgens) the whole surface sometimes 

 gives out a greenish lurid light which makes 

 it a most ghastly object, like some great 

 ravenous spectre. 



THE OCEAN DEPTHS 



The Land bears a rich harvest of life, but 

 only at the surface. The Ocean, on the con- 



