The language of wild animals language is the means by which men and animals A express their thoughts. Of language there are four kinds: vocal, pictured, written and sign language. Any vocal sound uttered for the purpose of conveying thought, or influencing thought or action, is to be classed as vocal language. Among the mammals below man, speech is totally absent; but parrots, macaws, cockatoos and crows have been taught to imitate the sound of man's words, or certain simple kinds of music. The primitive races of mankind first employed the sign language, and spoken words. After that comes picture language, and lastly the language of written words. Among the Indians and frontiersmen of the western United States and Canada, the sign language has reached what in all probability is its highest development, and its vocabulary is really wonderful. The higher wild animals express their thoughts and feelings usually by sign language, and rarely by vocal sounds.
