Stephen's eyes swept around the desert absently. He knew--this young man--that he was in the presence of a personality. For he could not help but draw comparisons between the young woman beside him and the young women of his acquaintance in the East. While he had found Eastern girls vivacious, and attractive with a kind of surface charm, never had he known one to take so quiet and unassuming an outlook upon so broad a theme. It was the desert, he told himself. Here beside him was a type unknown to him, and one so different from any he had as yet met with, he felt himself ill at ease in her presence--a thing new to him, too--and which in itself gave him cause to marvel. Yes, it was the desert. It _must_ be the desert! In this slender girl beside him he saw a person of insight and originality, a girl assuredly not more than twenty years of age, attractive, and thoroughly feminine. How ever did they do it? He harked back in his thoughts to her theory. And he dwelt not so much upon the theory itself as upon her manner of advancing it. Running back over these things, recalling the music of her voice, together with her spoken musings, he came to understand why, with that first encounter, he had found himself almost instantly curious concerning desert folk. Not that he had known why at the time, or had given that phase of it consideration. He did remember that he had been strongly impressed by the way she had managed her bolting horse. But aside from that, there had been something in her personality, an indefinable calm and sureness, a grip upon herself, that he had felt the very first moment. Undoubtedly all this had flicked him into a novel curiosity. He pulled himself together with an effort. "I like your theory," he answered, smiling. "And it must be true, because I am told horned toads are fast disappearing. Evidently they have served their purpose. But tell me," he concluded, "what is becoming of them? Where are they going?" She laughed. "I can't tell you that. Perhaps they just vanish into the fourth--or maybe the fifth--dimension!" And this was the other side of her, a side he had come to learn while with her at the dance, and which made her lovable as well as admirable. But she was speaking again, and again was serious. "I have yet another theory," she said--"one as to why these creatures are here, you know." She smiled across at him. "It is all my very own, too! It is that in their presence among us--among mankind--they unwittingly develop us through thought. Thinking exercises the brain, we are told, and exercising the brain makes for world-advancement--we are told." Then, suddenly, "I hope you don't think me silly--Mr. Native?"