WA TER FLEAS. 



137 



ing. The two powers which move the human world, 

 love and hunger, seem to reign quite as predominantly 



Fig. 97- 



Fig. 98. 



Water flea (Daphnia pulex) 

 male, enlarged to correspond- 

 ing proportion as Fig. 97. 



Water flea (Daphnia pukx) female, magnified 

 to show internal organs. The small figure en- 

 closed within a circle shows the natural size. 



among animalcules. It is not " live and let live," 

 however, which is their rule ; but " might is right ! " 



