Strange Tomorrows, a reprint-anthology edited by Robert Hoskins. Original appearances from 1950 to 1958 - in Thrilling Wonder Stories, Venture, Astounding, and Satellite S.F.. These are long pieces - novella length. The Clement piece is the first time the author's orginal version appears - when he submitted it to Satellite S.F., the editor (Merwin) added his own Earthling-viewpoint alternating chapters to bulk it out to "novel" length (without consulting Clement.)

(Introduction by Robert Hoskins)
"Shadow on the Sand" by John D. MacDonald
"The Comedian's Children" by Theodore Sturgeon
"Firewater!" by William Tenn
"The Greatest Invention" by Jack Williamson
"Planetfall" by Hal Clement.