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WAS THIS iiiK iiitsi I oKM <)i III i: ON 1111. <;l(>im:? 



BliK-gn-cn algae (N'ostocateae) such as are shown above, about 800 times natural size, are 

 little (lifierent from bacteria in structure. They can live in hot springs and get their 

 ffKid exclusively from minerals. Euler suggests that they represent the earliest living 

 thing in the world; if .so, their sjwres must have been brought here from some other ])lanet, 

 proi)elled by waves of light. Unless thev came from our own .solar system, they must 

 have travelled for at least 9,000 years before reaching the c^irth. Photomicrograph by 

 John Howard Paine, from a i)rei)arali()n by II. L. Shantz. (Fronti.s])iece.) 

 See "A Hit-or-Miss Univ.Tse," p. .520. 



