52 MEDICAL MYCOLOGY 



Growth is slow on this medinm since the peptone furnishes both carbon and 

 nitrogen, but pleomorphism of the dermatopliytes is greatly delayed. Per- 

 sonally, following a suggestion of Thaxter who had long experience with 

 other groups of fungi in culture, I prefer to add 40 gm. of agar instead of 

 18 gm. to media to be used for stock cultures. Growth is extremely slow and 

 the cultures do not dry out so rapidly, both of which conditions are advanta- 

 geous with routine stock cultures, as the labor of preparation of media and of 

 transfer is greatly reduced. 



For isolation and study of the organisms, Sabouraud's test agar (1908), 

 commonly called Sabouraud agar, contains 40 gm. of crude maltose. Sabour- 

 aud has been severely criticized for using the crude sugar, as samples vary 

 greatly, one sample used by Sabouraud on analysis yielding mostly glucose 

 (Hodges 1928). For most organisms glucose gives equally good growth, in 

 fact pure maltose is generally poorer. There seems little difference whether 

 10 or 40 gm. per liter are added. The firm from which Sal)ouraud secured 

 his maltose ceased business during the World War (1914-1918) and since then, 

 much research has been expended to secure a substitute product which will 

 produce the same giant colonies as those figured by Sabouraud (1910). Sab- 

 ouraud himself (1925) advocates the use of 8% honey, but again introduces 

 a source of error, since honey varies very much according to the species of 

 bee producing it and the flowers from which it is made; e.g., Berde (1926) 

 failed to secure characteristic colonies on honey made from flowers of Rohinm 

 or Stachys annua. 



Weidman «& Macmillan (1921) and Weidman (1928) in very extensive 

 studies found that crude glucose gave equally good results, Fairchild's peptone 

 being used instead of Chassaing. This medium is often referred to as the 

 Pennsylvania medium. 



Goldschmidt (1924) proposed the following for English laboratories: 



Glucose 40 gm. 



Agar 20 gm. 



Peptone (Fairchild) 10 gm. 



Lemco (ordinary not laboratory) 5 gm. 



NaCl 5 gm. 



Tap water 1000 c.c. 



Lemco is an acid meat extract. Ingredients digested in a steamer for 1 hour, 

 adjusted by "soda" to pH 6, sterilized 20 minutes each on 3 successive days. 

 Gruetz (1923) proposed the following for German laboratories: 



Peptone (Knoll) 5 gm. 



Nervina Malz from Christiansen, Flensburg 80 gm. 



Agar IS gm. 



Water 1000 c.c. 



Pollacci (1922) proposed the following for Italian laboratories: 500 gm. 

 ground beef in 1000 c.c. water; cook and filter; add 100 gm. Witte peptone, 

 5 gm, sodium chloride ; heat, filter, warm, and neutralize ; heat for half an 



