brilliant tinge of red by day. The amazing spec- 

 tacle of phosphorescence is produced by many vari- 

 ous forms of these animals, but the commonest 

 light-producers of all are the species of Noctiluca. 

 Actually, they are not often larger in diameter 

 than a pencil dot ; but the species Noctiluca miliaris 

 now magnified under the lens of my microscope 

 looms up as large as an apple. And not greatly 

 unlike an apple is it in general; what stands for 

 the stem is in Noctiluca a long pointed process 

 resembling a heavy lash. At the base of this lash, 

 or flagellum, is the mouth, a groove-like orifice 

 reaching nearly half-way around one side. From 

 the mouth extrudes a much smaller and finer hair- 

 like organ, the second flagellum. As in the case of 

 all other Dinoflagellata, in life it swims with the 

 help of the large flagellum; the smaller flagellum 

 it uses to capture food. Though Noctiluca consists 

 of but a single cell, it lives and eats in the manner 

 of its larger neighbors in the sea whose bodies are 

 composed of a billion or more; despite its mi- 

 nuteness and simple structure it preys upon other 

 organisms still smaller, and is seemingly able 

 readily to detect by the merest touch the difference 



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