Jan. 14, 1918 Cultures of Wood-Rotting Fungi on Artificial Media 35 



triangular section cut out of the aluminum screw top large enough to 

 hold the plug from the mother tube, and a salt-mouth bottle (holding 300 

 or 400 c. c.) filled about two-thirds full with 95 per cent alcohol. The 

 blades of the scissors used in making the transfers are kept in this 95 

 per cent alcohol when not in actual use. The glass jar and top are cleaned 

 by washing in hot water and then dried before using. The opening in the 

 top is thoroughly flamed over an alcohol lamp or Bunsen burner and the 

 jar is placed on its side with the triangular opening toward the operator. 

 During the actual inoculation the cotton plug from the mother tube is 

 placed in the triangular opening with the lower end of the plug inside the 

 jar in such a manner that only the sharp edges of the top of the jar come 

 in contact with the cotton plug. In this position the plug is protected 

 from outside contamination and at the same time the hands of the 

 operator are left free to handle the scissors, two culture tubes, and the 

 cotton plug from the tube to which the transfer is being made. 



In making the transfers of certain standardized series it was necessary 

 to obtain small inocula as near the same size for each transfer as possible. 

 The ordinary inoculating needles and loops made either of platinum or of 

 iridio-platinum are too soft and in other ways unsuited for making 

 transfers of fungus mycelium. The writers therefore adopted the use of 

 the scissors for such work, since by using them the mycelial layer on the 

 surface of the agar in the culture tubes can be readily cut and any desired 

 size of inoculum transferred without loss of time and with a minimum of 

 outside contamination. 



VEGETATIVE CULTURAL CHARACTERS ON ARTIFICIAL MEDIA 



MEDIA USED 



In studying the cultural characters of the various fungi as outlined 

 under No. i of the introduction, the following general system was adopted : 

 A series of 10 different culture media in agar was used for each fungus. 

 These 10 media were (i) 1.5 and 2 per cent carrot agar, +3.5 to +5.0; 

 (2) 1.5 and 2 per cent malt agar, +7.0; (3) 1.5 per cent beet agar, +2.5 

 and +3.0; (4) 1.5 per cent celery agar, +9.5 to +15.5; (5) i-5 per cent 

 bean agar, + i.o to +1.5; (6) 1.5 and 2 per cent corn-meal agar, +0.25; 

 (7) 1.5 and 2 per cent prune agar, +1.0 and +1.5; (8) 1.5 and 2 per 

 cent alfalfa agar, +13.5 to +15.5; (9) i-5 per cent parsnip agar, 4-9.0 

 to + 13.5; and (10) 1.5 and 2 per cent potato agar, +2.0 and +3-5- The 

 acidity of the media here given is based on Fuller's scale and is the actual 

 acidity of the media after tubing and as used in the cultures. 



In any series of a given fungus each corresponding agar for each strain 

 had the same percentage and the same acidity. For instance, there were 

 nine strains of Trametes pint compared. The carrot agar used for each of 

 these nine sets was 2 per cent and had an acidity of +3.5. 



The writers selected the 10 media for the study of the cultural characters 

 of the different fungi not with a view to obtaining vigorous growth but 



