pairs, but sometimes joined together in thread-like forms. The second organism, called by me “bacillus _e_,” forms small brownish-yellow boat-shaped colonies on gelatin plates. The bacteria consist of plump cells two or three times the size of bacillus _d_, united in pairs and chains, but the cells vary considerably in size, and are surrounded by a capsule. I have discovered that the above bacteria, when used separately as pure cultures, exert little or no action on the skin, but when used together the action is very remarkable. The gelatin and gelatin plates referred to in the above description are the gelatin and gelatin plates used for the cultivation of bacteria, according to the ordinary bacteriological methods as described in Günther’s “Bakteriologie,” published by George Thieme, Leipzig, in 1898, and in other text-books. In the accompanying drawings, made from photographs which are of record in this case, the bacillus _d_ is shown in Fig. 21, and the bacillus _e_ in Fig. 22, both photographs showing the bacilli magnified 1000 diameters. A culture may be prepared from the sweating bacteria by taking the hair from the skin when it “slips”--that is, when it can be removed by simply pulling it. The root portion of the hairs are then cut off, and about 10 grm. carefully digested in 100 c.c. of water at a temperature of 32° to 35° centigrade for several hours. The liquid portion is then poured off, and used for inoculating 10,000 c.c. of a nutrient medium of the character hereinafter described. The inoculated nutrient medium is then maintained for three days at a temperature of 37° centigrade, and may then be used for the inoculation of a larger quantity of nutrient medium. Theoretically, a single cell of a bacterium is sufficient to inoculate any quantity of any suitable fluid; but in practice it is found necessary or expedient to employ 5 or 10 per cent. of inoculating matter to the volume of the liquid to be inoculated. The inoculation of the 10,000 c.c. of nutrient medium may be done in a Carlsberg vessel, as described by Hansen in his “Untersuchungen aus der Praxis der Gärungsindustrie.”