F-156 AT THE EARTH’S CORE The discovery of the inner world and adventures therein in a land that remained in the Stone Age! F-157 THE MOON MAID The spaceship Barsoom breaks into the hidden civilization of the moon! F-158 PELLUCIDAR The empire inside the Earth is thrown into turmoil by a conspiracy of monsters. F-159 THE MOON MEN Two novels telling of the future of the Earth after its conquest by treachery and Lunar science. F-168 THUVIA, MAID OF MARS A terrific novel of adventure on the dead sea bottoms of John Carter’s planet of war. F-169 TARZAN AND THE LOST EMPIRE Tarzan of the Apes finds new peril when he discovers the last of the Roman legions. F-170 THE CHESSMEN OF MARS A kidnapped princess is the prize in a game of life and death. F-171 TANAR OF PELLUCIDAR A primitive chieftain dares the terror of pirate firearms. F-180 TARZAN AT THE EARTH’S CORE The Lord of the Jungle vs. Pellucidar! Ask your newsdealer for them. If he is sold out, any of the above books can be bought by sending 40¢, plus 5¢ for handling costs, for each book to ACE BOOKS, INC. (Sales Dept.), 1120 Avenue of the Americas, New York 36, N.Y. Here’s a quick checklist of recent releases of ACE SCIENCE-FICTION BOOKS 35¢ D-547 THE SUPER BARBARIANS by John Brunner D-550 NO WORLD OF THEIR OWN by Poul Anderson D-553 THE HOUSE ON THE BORDERLAND by Wm. H. Hodgson D-555 THE TRIAL OF TERRA by Jack Williamson 40¢ F-141 THE DARKNESS BEFORE TOMORROW by Robert. M. Williams and THE LADDER IN THE SKY by Keith Woodcott F-145 THE SEED OF EARTH by Robert Silverberg and NEXT STOP THE STARS by Robert Silverberg F-147 SEA SIEGE by Andre Norton and EYE OF THE MONSTER by Andre Norton F-153 THE SWORD OF ALDONES by M. Z. Bradley and THE PLANET SAVERS by M. Z. Bradley F-154 THE WIZARD OF LINN by A. E. Van Vogt F-161 TIMES WITHOUT NUMBER by John Brunner and DESTINY’S ORBIT by David Grinnell F-162 BEST FROM FANTASY & SCIENCE FICTION: 7th Series F-167 CATSEYE by Andre Norton F-173 SECOND ENDING by James White and THE JEWELS OF APTOR by Samuel Delany F-174 FIRST THROUGH TIME by Rex Gordon F-178 MORE ADVENTURES ON OTHER PLANETS Edited by Donald A. Wollheim If you are missing any of these, they can be obtained directly from the publisher by sending the indicated sum, plus 5¢ handling fee, to Ace Books, Inc. (Sales Dept.), 1120 Avenue of the Americas, New York 36, N.Y. THE CREATOR OF “TARZAN” EXPLORES A FOREST PLANET When Carson Napier’s giant rocket crash-landed on the planet Venus, he knew that there would be no return to Earth for him. His problem was to survive somehow until other Earth rockets could follow.