XI. Studies on some new micro-organisms obtained from air

In some papers on the micro-organisms present in air, previously communicated to the Royal Society by one of us, the relative abundance of microbes in the air of different places has been called attention to and the methods of experiment fully described. As these investigations were carried out with the aid of solid nourishing media, we were able to obtain a collection of pure cultivations of a number of micro-organisms derived directly from the air. It appeared to us, therefore, desirable to utilise the opportunity which these experiments furnished for minutely characterising some of the principal forms which are thus obtainable from the atmosphere. There are many reasons which render it of importance that the task in question should be undertaken. Thus, in the methods of cultivation employed by bacteriologists, the experimenter may at any moment be brought face to face with organisms from the air which have accidentally contaminated his cultivations, and it is obvious, therefore, that an intimate acquaintance with the various forms which may thus invade culture-media must be both of interest and importance to all practically engaged in experiments on micro-organisms. It is not unnatural that the brilliant discoveries in connection with the etiology of infectious diseases should have absorbed the lion’s share of the attention of investigators in the field of bacteriology, and that the non-pathogenic organisms should have come to be regarded as comparatively uninteresting by the side of their more formidable brethren. It must, however, be remembered that the functions of the non-pathogenic organisms in the economy of nature are as yet but very imperfectly understood, and that as far as these functions have been investigated they do not yield in point of importance to those of the most virulent pathogenic forms.