144 J. F. Fitzpatrick, Jr. 



the specifics of microdistribution patterns should reveal much of the 

 geologic, as well as the faunistic, history of the eastern Mississippi 

 Embayment. Correlation of these results with reinterpretation, based on 

 the more recent datings of "Citronelle" deposits, of faunistic patterns to 

 the east or west of the Embayment promises to illuminate the manner in 

 which aquatics populated the southern part of the North American 

 continent. 



ACKNOWLEDGMENTS.— As always, I benefited greatly from 

 conversations and exchanges of ideas with Horton H. Hobbs, Jr. He 

 and Perry C. Holt read an early draft of this manuscript, and their 

 criticisms contributed much to the development of my thinking. Wayne 

 C. Isphording is thanked for helping me to interpret the complex and 

 often very technical geological literature, and he provided Figure 6 

 (from Isphording 1983, Fig. 10); George M. Lamb helped with some of 

 the geomorphological concepts. 



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