222 



alkaline basalts to the situation exemplified, for example, 

 by the Hawaiian Islands. 



We thank the officers, men and scientists of cruise 20 

 (1966) of the R.V. Atlantis II. This work was supported 

 by the Snaithsonian Institution, the US Atomic Energy 

 Commission, the US Office of Naval Research and the US 

 National Science Foundation. We thank Dr V. T. Bowen 

 for his assistance. 



William G. Melson 

 Eugene Jarosewich 

 Richard Cifelli 



Smithsonian Institution, 

 Washington, D.C. 



Geoffrey Thompson 



Woods Hole Oceonographic Institution, 

 Woods Hole, Massachusetts. 



Received March 17; revised June 2C, 1967. 



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Ann. Meeting Oeol. Soc. Amer., 138 (1966). 

 » Melson, W. G., Jarosewich, E., Bowen, V. T., and Thompson, G., Seietice, 



155, 1532 (1967). 

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 ' Engel, A. E. J., Engel, C. G., and Haven, R. G., Oeol. Soc. Amer. Bull., 76, 



719 (1965). 

 « Engel, A. E. J., and Engei, C. G., Science, 146, 477 (1964). 

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