Lest Darkness Fall

US original and the true first edition worldwide; the census claim is correct. It expands the shorter version from Unknown (December 1939), which is a magazine appearance and not a book. The significant trap is the Prime Press (Philadelphia) 1949 edition, which ABAA and other dealers explicitly catalogue as "First Thus" — it is black cloth stamped in gilt and collates 233 pp., quite unlike the Holt sheets, and is a later hardcover reprinting rather than a first edition. Note also that a commonly repeated claim of a 1949 "Galaxy Publishing" reprint does not withstand scrutiny (the Galaxy Novels line did not begin until 1950) and is excluded here.