It felt more like a dozen friends around a campfire than a packed Ed Landreth Auditorium when one-third of the Peter, Paul and Mary singing trio graced the stage in July. Here for a benefit concert for the Camp Fire Boys and Girls, Peter Yarrow’s two-hour concert included a rousing rendition of “Puff, the Magic Dragon,” as well as the theme song for a new program he is promoting, Don’t Laugh at Me. Among the awestruck at an after-concert visit was Abby Womack, 11, who attended the concert with her parents, Stephanie and John Womack ’77 (the beaming father holding the camera in the background).