I AM GRATEFUL to the John Simon Guggenheim Memorial Foundation and to the Social Science Research Council for the material aid given to me for the field work that preceded the writing of this book.

Many individuals have been generous in reading parts or all of the manuscript: Carl O. Sauer, John B. Leighly, and Raymond I. Storie of the University of California at Berkeley; Jan 0. M. Broek of the University of Minnesota; Billie Lee Turner of the University of Texas; and Júlio Caro Baroja of the Museo del Pueblo Español, Madrid, Spain. None of them, however, should be penalized for their generosity by blame for any errors in my conclusions, or other deficiencies.

Very special gratitude goes to my wife for the great help that she has given me through all stages of inquiry and the preparation of the book.

I am indebted to the Instituto do Vinho do Porto for the photograph of the Douro River canyon that is used. To the dozens of other Portuguese and Spaniards who so generously helped me I offer my thanks. The list is too long to print.