358 THE OCEAN. 



tlie animals. A drop of sulphuric acid being put 

 into a glass of water, several bright flashes of light 

 were seen. One of the little animals was taken up in 

 a drop of water on the point of a pen ; on a drop of 

 acid being added, it gave out a momentary spark and 

 instantly died. Several new species of luminous 

 animals were discovered by thus mingling acid with 

 quantities of sea-water. The light of different spe- 

 cies is found to vary in character ; some of the sparks 

 being yellow and dull, others clearer and whiter, and 

 more lasting. The creature wliich produces the 

 brightest light of all is a kind of sea-worm {Nereis 

 cirrigera) ; it lives in groups or large masses, among 

 the branches of sea-weed ; and when portions of this 

 are thrown on shore by the waves, the animals sur- 

 vive and continue to shine very brilliantly for several 

 days. In our own seas, a great deal of the light is 

 owing to the presence of a minute animal (Nocfihtcd 

 miliaris), which does not exceed -oV of an inch in 

 diameter. It consists of a transparent globose body, 

 with a cleft down one side, as we often see in a 

 peach, or as if two globes had been fused into one. 

 Where the stalk would be, supposing it were a fruit, 

 a slender tentacle projects, which is endowed with 

 the power of slow and feeble motion. Just below 

 this tentacle there is a minute orifice which servos 

 as a mouth, leading to an oval granular stomach, 

 whence branched fibres proceed in irregular pencil? 

 to all parts of the circumference, resembling threads 

 of a very glutinous fluid. 



This little animalcule, to which, in these seas, so 

 much of our marine luminosity is owing, may be 



