PREFACE 



Because ot the long delay in issuing this bulletin, the reader should be aware that most of the doto 

 presented ore based on field work and literature review conducted from 1962 to 1965. The reader 

 is referred to the paragraph under Purpose and Time of Investigation (p. 3) for a more complete 

 explanation. 



Despite the delay in publication, the material presented here in believed to be largely valid and 

 useful. 



EARL W. HART 

 April 16, 1978 



VI 



