"I thought Dr. Gordon was at White Sands Proving Ground in New Mexico." "So did I," Scotty remarked. "The telegram was the first I knew about his working in Nevada." Barby held up her hand. "Listen!" A plane was in sight! Rick identified it as a prop-driven Navy utility job. No doubt of it, Gordon was arriving! They watched eagerly as the plane lost altitude, flaps and wheels lowered for the landing. The pilot brought it in over the big radar antenna on the laboratory roof, then dropped onto the runway for a three-point landing opposite the orchard. The three ran around the wing, bracing themselves against the prop blast. Rick took the suitcase that was handed to him by Dr. Gordon, who leaped lightly to the ground after his luggage. The scientist, a short, wiry man with gray hair cropped crew-cut fashion, waved to the pilot, then motioned the young people back as the pilot turned with a blast of his prop and taxied to take-off position in front of the lab. Because of the racket, no one tried to talk until the plane was nearly out of earshot. Then Barby spoke for all of them as they walked to the house. "We thought you'd never get here!" Dr. Gordon smiled his pleasure at being home again. He shook hands with the boys. "You've no idea how nice and green this island looks after the Nevada desert. And you've no idea how hungry I am! Is it too late for lunch?" Mrs. Brant answered him from the porch. "You have just two minutes to wash up and come to the table, John!" Hartson Brant appeared behind her. He shook hands with Dr. Gordon as the three young people escorted him to the porch. "Welcome home, John." "Thanks, Hartson. It's good to be back. Where are the others? Zircon, Weiss, and Winston? I know Tony and Howard are off on an expedition, but I thought the others were home." "They are. Parnell Winston is probably having lunch at his cottage. Hobart and Julius are in New York, examining some new equipment for the lab. They'll be back tonight." Rick was dying to ask questions, but he knew this was not the right time. At lunch, perhaps, they might be given some details. John Gordon looked at him and grinned. "Here's Rick Brant," he declared, "politely holding his tongue when he's about to pop like a firecracker with questions. Your self-control does you credit, Rick. Want one bit of data to chew on while you're waiting?" Rick gulped, then returned the grin. "Yes, sir!" John Gordon lowered his voice to a confidential pitch. "We have an enemy," he stated. "What kind of enemy may be seen clearly in the name by which he goes." He paused. "What name?" Rick asked impatiently. "_Homo Terrestrialis._" John Gordon turned and hurried upstairs to his room to wash up for lunch. Rick stared after him. What in the name of a simple-minded spacefish did that mean? _Homo Terrestrialis._ Man of Earth. Earthman! CHAPTER II Assignment: Rocket Base