156 HIDDEN BEAUTIES OF NATURE 



creature is an object of great beauty. Its diameter 

 is about the three hundred and sixtieth of an 

 inch ! 



Fig. 45. Cyphoderia, Fresh-water Rhizopods (after Leidy), ^lo^ of an inch in 

 diameter. 



In 1840, Ehrenberg wrote an elaborate account of 

 these rhizopods. They are found in the surface 



