Needle

The Hunter kept the eye in use during most of the underground search. His questing appendage at last reached sand that was more closely compacted than usual and, advancing very cautiously now, finally encountered what could only be living flesh. Robert's toes were buried in the sand, since he was lying on his stomach, and the Hunter found that he could operate without emerging at all to the surface. With that fact established, he dissolved the eye and drew the last of his mass out of sight below the sand-with considerable relief as the sunlight was cut off.

He did not attempt to penetrate until his whole body had been drawn through the sand and was wrapped about the half-buried foot. He surrounded the limb with extreme care, bringing himself into contact with the skin over several square inches. Then and only then did he commence interstition, letting the ultra-microscopic cells of his flesh slide through pores, between skin cells, under toenails-into the thousands of openings that lay unguarded in this, to his way of thinking, singularly coarse organism.

The boy was sound asleep, and remained so; but the Hunter worked as fast as possible nevertheless, for it would have been extremely awkward to have the foot move while he was only partly inside. Therefore, as swiftly as was compatible with extreme caution, the alien organism flowed smoothly along the bones and tendons in foot and ankle; up within the muscle sheaths of calf and thigh; along the outer wall of the femoral artery and through the tubelets within the structure of the thigh bone; around joints, and through still other blood vessels. It filtered through the peritoneum without causing sensation or damage; and finally the whole four pounds of unearthly life was gathered together in the abdominal cavity, not only without harming the boy in the least but without even disturbing his slumber. And there, for a tune, the Hunter rested.

He had a bigger oxygen reserve this time, having entered from air rather than water. It would be some time before he needed to draw on his host for more. He was hoping, if it were possible, to remain exactly where he was for an entire day, so that he could observe and memorize the cycle of physiological processes which this host undoubtedly performed differently from any he had known before. At the moment, of course, the creature was asleep, but that would probably not be for long. These beings seemed pretty active.

Bob was aroused, like the other boys, by the sound of his mother's voice. She had come silently, spread a blanket in the shade, and arranged the food on it before speaking; and her first words were the ancient "Come and get it!" She would not stay to help them eat it, though cordially and sincerely pressed to do so by the boys, but went back through the palm grove to the road that led to their home.

"Try to be back by sundown," she called to Bob over her shoulder as she reached the trees. "You still have to pack, and you'll have to be up early in the morning." Bob nodded, with his mouth full, and turned back to the food-laden blanket.

After disposing of the meal, the boys sat, talked, and dozed for the standard hour after eating; then they returned to the water, where they indulged further in games of violence; and at last, realizing that the abrupt tropical night would soon be upon them, they gathered up the blanket and started for the road and their respective dwellings. They were rather silent now, with the awkwardness natural to their ages when faced by a situation which adults would treat either emotionally or with studied casualness. The farewells, as they passed their respective dwellings, were brief and accompanied by reiterated and reciprocated promises to "write as soon as you can."

Bob, proceeding at last alone to his own house, felt the mixture of regret and pleasurable anticipation which he had come to associate with these occasions. By the tune he reached home, though, the latter feeling had gained the ascendant, and he was looking forward with considerable eagerness to meeting again the school friends he had not seen for more than two months. He was whistling cheerfully as he entered the house.

The packing, done with the tactful assistance of his mother, was quickly completed, and by nine o'clock he was in bed and asleep. He himself considered the hour rather early, but he had learned the value of obedience at certain times very early in life.

The Hunter was able to remain quiescent, as he had hoped, for some hours-till well after Bob was asleep, in fact. He could not, however, last an entire day; for no matter how quiet he remained, the mere fact of living used up some energy and consequently some oxygen.

Eventually he realized his store was growing low, and he knew it would be necessary to establish a supply before the need became desperate.

He knew, of course, that his host was asleep, but this in no way decreased his caution. He remained for the time being below the diaphragm, not wishing to disturb in any way the heart he could feel beating just above it; but he was able to find without effort a large artery in the abdomen which offered no more resistance to penetration than had any other part of the human organism thus far. He discovered, to his intense satisfaction, that he could draw enough oxygen from the red cells (he did not think of them by color, since he had not yet seen them) to supply his needs without seriously diminishing the quantity that passed through the vessel. He checked this fact very carefully. His whole attitude in the present exploration was utterly different from that which had directed his actions within the body of the shark, for he had come to look upon Robert in the light of a permanent companion during his stay on the earth, and his present actions were ruled by a law of his kind so ancient and so rigid as to assume almost the proportions of an instinct.

Do nothing that can harm your host!

Chapter III. OUT OF PLAY

Do nothing that can harm your host! For the majority of the Hunter's kind even the desire to break that law never existed, since they lived on terms of the warmest friendship with the beings whose bodies harbored theirs. The few individuals who proved to be exceptions were regarded with the liveliest horror and detestation by their fellows. It was one of these whom the Hunter had been pursuing at the time of his crash on the earth; and that being, he well knew, must still be found-if only to protect this native race from the inroads of the irresponsible creature.

Do nothing that can harm your host! From the moment of the Hunter's arrival the swarming white cells in the boy's healthy blood had been aroused. He had avoided the most serious contacts with them up to now by keeping clear of the interiors of blood vessels, though there were enough of them wandering free in the lymphatics and co