258 BOTANICAL GAZETTE [October 



Standard beef gelatin: according to the rules of the American 

 Public Health Association. 



Pure agar: i per cent, agar without addition of nutrients. 



Litmus lactose agar: standard beef agar with the addition of i per 

 cent, lactose, and litmus sufficient to color. 



Lettuce agar: 10 grams of lettuce leaves and petioles were stewed 

 in water for one half -hour, drained, i per cent, agar added, auto- 

 claved at 110°, and filtered. 



Boiled rice: 2 grams of washed rice to 8^^ of water, tubed, auto- 

 claved at 110°. 



Boiled corn: 2 grams of washed corn to 8*^^ of water, tubed, auto- 

 claved at iio^. 



Glucose agar and starch agar: made by adding percentages indi- 

 cated to pure agar, and sterilizing intermittently. 



Peptone agar: made by adding per cent, indicated to pure agar 

 and autoclaving at iio*^. 



West Raleigh, N. C. 



