English translation of Heinrich Anton de Bary's 1878 speech, 'Die Erscheinung der Symbiose' ('De la symbiose')

Die Erscheinung der Symbiose, meaning the phenomenon of symbiosis in English or de la symbiose in French, is a transcription of the 1878 lecture by the German botanist and mycologist Heinrich Anton de Bary in which he first used the term 'symbiosis' in a biological context. De Bary's speech was published in 1879 in German, later to be translated into French; though only fragments of his speech are available in English. Translating de Bary's lecture is timely because the field of symbiosis, especially with respect to microorganisms, is expanding and the importance of symbiosis is now recognized across the biological sciences. Researchers have now begun to sort through the early literature to uncover original thoughts pertaining to symbiotic interactions. We believe that having de Bary's lecture accessible to researchers in English will help enhance interest in the history of symbioses, document de Bary's pioneering contribution, and aid in establishing an understanding for whom the lecture was intended and when biological symbioses were first recognized. We present a short biography of Heinrich Anton de Bary, a full translation of his lecture, and conclude by briefly highlighting current endeavors in symbiosis research.