Edward Everett Evans, Man of Many Minds — Chapter 14 (1953)
“ That gave him the idea for an experiment, and he started whistling as loud as he could, gradually raising his tones until he was at the top of his range. He saw with interest and excitement that the last one or two shrillest notes seemed to attract their attention. Their silly-looking little triangular ears perked up and began twitching. They turned about, as though seeking the source of that sound, while every mouth began working with signs of utmost excitement, and his mind caught concepts of surprise and wonder. ”
