In preparing the enlarged third edition, many of the above mentioned friends have again helped me. I have picked the brains of Professor F. Clark Howell of the Department of Anthropology of the University of Chicago in reworking the earlier chapters, and he was very patient in the matter, which I sincerely appreciate.

All of Mrs. Susan Richert Allen’s original drawings appear, but a few necessary corrections have been made in some of the charts and some new drawings have been added by Mr. John Pfiffner, Staff Artist, Chicago Natural History Museum.

Robert J. Braidwood

March 1, 1959