5 



soil and air. Human faeces were coUected ex ano in sterilized 

 widemouth 150 c. c. bottles. The samples af animal faeces tested 

 had in most cases to be collected on the floor of the cage, but 

 precautions were laken to avoid contamination as much as possible. 

 Only fresh dung, a few minutes old at the most, was used. The 

 outer particles were removed and with a scalpel repeatedly flamed 

 over an alcohol lamp the central parts of the excrements were dug 

 out and put in steriHzed bottles. In order to obtain satisfactory 

 emulsions approximately 5 grams of the faeces were shaken for 

 10 minutes in 50 c. c. of distilled water. A few cubic centimetres 

 of this emulsion were poured into test tubes containing the media, 

 shaken, and then plated. If the samples were known to contain 

 an abundance of spores the procedure was somewhat different. 

 A few cubic centimetres of the spore-containing emulsion were trans- 

 ferred from the first test tubes into a second containing the media, 

 and again after vigorous shaking a few dröps were transferred from 

 the second to a third. The contents of these tubes were then 

 transferred to Petri dishes. By this method the spores were 

 distributed singly, and a pure culture from a single spore was 

 readily obtained. The Petri dishes obtained from the same sample 

 of faeces were divided into two lots; one was incubated at 37^ C. 

 for 12—24 hours, the other was kept at room temperature for 

 24—48 hours. The plates wwe then examined under a dissecting 

 microscope, and transfers were made to test tubes containing the 

 ordinary media. 



3. Results of the Isolations. 



Samples of faeces w^ere obtained from 13 different persons, two 

 of them being vegetarians. Whenever possible, several samples 

 from the same person were examined. The date of examination 

 is given in every case. 

 Mixed diet A. 



March 2, 1914: Aspergillus fumigatas, A. nidulaiis, Macor} 

 March 6: Aspergillus fumigatas, A. niger. 

 Mixed diet C. 



Jan. 6, 1915: None; Jan. 13: Yeasts; Feb. 15: None; March 3: 

 None. 

 Vegetarian E. 



March 2, 1914: Aspergillus terreus, A. niger, A. umbrinus. 



^ The cultnre was lost by an accident before any further determination had 

 been made. 



