The Plenary Sessions At six of the pleMly sessions, the presemationwas given by one speaker. At three others,c a i l d plenary
tandem lectures, two speakers addressed a single topic. each 1rom.i different viewpoint. A summary of each plenary lecture is given below. For the lectures presented by one speaker. this summary consists of an abstract followed by selected paragraphs from the address. For the plenary tandem lectures, the summary includes abstracts and selected paragraphsfrom each presentation, followed by highlights from the discussion that followed the talks. All of these talks will appear in their entirety in the "Proceedings."
The Sunday Evening Lecture
Cosmochemistry and the Origin of Life Cyril Ponnamperuma Professor of Chemistrv and Director. Laboratow of Chemical Evolution University of ~atyland,College Park, MD 20742
Abstract Life is considered to he the inevitable consequence of the evolutionary process in the universe. Laboratory experiments have clearly demonstrated that the components of the nucleic acids and proteins can be formed in simulated primitive planetary e&ironments. Amino acids of extraterrestrial origin have been identified in a number of carbonaceous chondrites. A vast arrav of oreanic molecules. intermediates in rimo or did organic chemistry, have been recognized in the interstellar medium. These observations stronelv sueeest that chemical evolution is cosmic in nature anJihatw
