IT is evident from a fairly large number of published sources and living folk beliefs, and from certain types of literary creations (fables, tales, songs), that branches of South Slavs-Slovenes, Croats, Serbs, Montenegrins, Macedonians, Bulgars-imagine that entire animal and vegetable world and things and phenomena in nature, even when they lose signs of life, can express their feelings and thoughts by means of certain utterances, sounds, or rustlings. They also believe that these means of communication can in certain cases be brought to humans, and that this special knowledge is property from beginning of certain supernatural beings, saints, rulers, and various other persons, specified or unspecified. It is further believed that this power of expressing thoughts and feelings can be received, or won, under specific conditions even by certain ordinary people. This spiritual method of conveying meaning has received various names, or terms, among South Slavs, some of which are special, while others are more general in scope: the ox language, the frog language, the jackdaw language, the swallow language, the bird language, the animal (or speech), every (or all languages), the language which is stuck on, the bribeless language, and the secret language. There are also expressions silence, the language that is not, language, the mute voice, the language of and, finally, (nemusti jezik) in various dialectal and colloquial forms. This expression is found among Serbs and Montenegrins and with some Croats and Macedonians, while other branches of South Slavs (except for one closely-related example among Slovenes) do not have it. Of material in which only this term appears, are included who know this language in any of its forms, general or specific, as mentioned above. It is clear from its first word, origin of which is uncertain, that expression means a language which has been invented-in which one mutes, deadens sound, or mumbles, but does not speak. Its sounds are like those which mute people make, or, in general, sounds of animals, birds, and others heard in nature. Because of unusual construction of word nemusti, with Church Slavonic suffix -usti, and because of meaning that people associate with concept of in material, this expression corresponds most precisely to entire belief in a speech of animate and inanimate world and natural phenomena, and of certain beings and persons. It is truly nomen est omen, and it is difficult to find a proper substitute for it in any language outside Serbo-Croatian.2 The South Slavic peoples believe that mute language is known or used, first of all, by entire animal kingdom, without regard to species or their relations to