4 



Grunde.» In no case has a determination of the fungi been made. 

 Gao (5), who made a special study of the genus Oidium, isolated 

 many »species» and demonstrated the abundance of pathogenic 

 and non-pathogenic Oidium forms in nature. He found species of 

 this genus in faeces from the foUowing animals: sheep, calf, rat, 

 rabbit, chicken, and slug. Ankersmit (2), studjdng the bacterial 

 flora of cattle excrement reports colonies of moulds growing on 

 material plated from the reticulum of a cow, but Avhithout any 

 determinations. Weigmann and Wolff (69) found Penicillium 

 brevicaiile repeatedly in the faeces of cow and attributes to this 

 fungus the peculiarity of giving the mvistard taste to milk and 

 butter when cows are being fed on cabbage. Wuthrich and Freuden- 

 REicH (71) found Oidium lactis in faeces of^ a cow fed on sour 

 potatoes. HoPFE (29) reports the presence of »moulds and yeasts » 

 in the digestive apparatus of Cricetus frumentarius. In one case 

 the fungus was determined to be a Mucor. 



2. Preparation of Media and Methods of Isolations. 



Before taking up for consideration the results of the isolations 

 it seems advisable to give a few remarks on the technic employed 

 in taking samples, in obtaining pure cultures, etc. Needless to 

 say, all Petri dishes were carefully sterilized for three hours a t 

 about 150^ G. All other glassware, including test tubes, bottles 

 and fläsks, was sterilized in the hot air sterilizer for about three 

 hours at 150^ G. The media used in this investigation was (except 

 when otherwise stated) the one commonly in use in this laboratory 

 for the growing of all ordinary fungi, and referred to as potato 

 agar. In making this media 18 — 20 grams of agar-agar were 

 melted either in an autoclave or över a gentle fire. While this 

 was being done an average-sized potato was pared, sliced, and 

 boiled in about half a litre of water for half an hour. The liquid 

 was strained through a double thickness of cheese cloth and added 

 to the melted agar. To this mixture was also added a table- 

 spoonful of cane sugar and enough water to make a litre. When 

 these ingredients were thoroughly mixed the medium was put into 

 test tubes and sterihzed in the autoclave for 30 minutes at 20 

 pounds pressure. 



In collecting the samples great care was exercised to exclude 

 every possible chance of contamination by fungous spores in the 



