BY THE SEASIDE—ANIMAL LIFE 



without heat and it is not uncommon in nature. 

 Glow worms and fireflies are phosphorescent; fish, 

 also, in the dead state, often emit a certain amount 

 of light as do bones whilst, of course, phosphorous 

 itself is the best example of a naturally phosphor- 

 escent body. Phosphorescent sea water, however, 

 owes its peculiarity to myriads of minute animals 

 and they will afford us an interesting half hour with 

 the microscope. Let us collect a little of this water 

 in a glass jar and take it into a darkened room 

 that we may the better see the phosphorescence. 

 When the water in the jar is undisturbed, we can 

 see nothing unusual, if we stir it or strike it a faint 

 greenish light is given off, but it does not last for 

 long. Now, on taking the jar into the daylight, as 

 soon as our eyes are accustomed to the light, we 

 shall just be able to see that there are some very 

 small living creatures on the surface of the water. 

 We must examine one, under a fairly high magnifir 

 cation; it may be transferred, from the jar to a 

 drop of water on our slide, by means of a paint 

 brush. The little animal which is responsible for 

 the phosphorescence of sea water is strangely remi- 

 niscent of an apple with its stalk. It is, of course, 

 very minute being only 1/60 inch in diameter and 

 its tail, which we have compared to the stalk of the 

 apple, is equal to the diameter in length. The 

 whole creature is quite transparent. As we 

 watch it swim in our drop of water, we shall 

 notice that it propels itself by the lasting of 

 its tail. 



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