244 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1961 



Figure 2. — Right: The author's chart of the major events in the evolution of life on our 

 planet. The compressed scale (inset) shows some very early events in the earth's history. 



equal to those given by H. C. Urey for the primitive atmosphere of 

 the earth. 



Calvin also discovered organic compounds in meteorites. Very 

 recently B, Nagy, D. J. Hennessy, and W. G. Meinschein detected 

 paraffinic hydrocarbons, closely akin to those found on earth in living 

 matter, in a fragment of a stony meteorite that fell in France nearly a 

 century ago. They believe this to be the first empirical evidence for 

 the existence of life beyond our own planet. Such an interpretation 

 has not been unanimously accepted by authorities on this subject. 

 However, if the meteorite's hydrocarbons are not due to contamination, 

 they indicate definitely that the formation of organic compounds is not 

 limited to the surface of the earth, although the mechanism of forma- 

 tion may be debated for a long time to come. 



