PETROGLYPHS— STEWARD 425 



and New Mexico, perhaps dating from several periods and exhibiting 

 marked local differences, have been published by E. B. Renaud in 

 Pictographs and Petroglyphs of the High Western Plains, 8th Re- 

 port of the Archeological Survey of the High Western Plains. Uni- 

 versity of Denver, 1936. 



Starting soon after the arrival of European colonists in America, 

 individual petroglyphs became the center of undeserved attention, so 

 that to this day we have a voluminous argumentative literature con- 

 cerning a few stones but virtually no broad, comparative studies 

 which bring perspective into large areas. At various times the Digh- 

 ton Rock, mentioned above, the Piasa petroglyph near Alton, HI., 

 and others have been discussed vehemently. Thanks, however, to 

 Delabarre's efforts, a large bibliography on New England petroglyphs 

 has been assembled. Donald Cadzow has added interesting material 

 in Petroglyphs in the Susquehanna River near Safe Harbor, Penn- 

 sylvania, Publications of Pennsylvania Historical Commission, vol. 

 3, 1934. Petroglyphs from many eastern States were reproduced 

 by Mallery. 



