26 



MUSHROOM GROWING AND SPAWN MAKING. 



It seemed possible, however, that some slight advantage resulted from 

 the calcium compounds, but there was no pronounced benefit in any 

 tube. Further reference is made to the use of nutrient salts in mush- 

 room growing in another chapter. 



Growth on chemically known media. — In an attempt to determine 

 somewhat more accurately the value of different compounds as 

 nutrients, particularly carbohydrate and nitrogenous substances, sev- 

 eral series of extensive tests have been made with Agaricus camfes- 

 tris, and also with Agcmcus fahaceus and Goprinus comatns. These 

 fungi do not grow readily in liquid media, and it has been difficult 

 to obtain a wholly reliable and satisfactory substratum, one which 

 would itself be practically pure, or well known, chemically, and at 

 the same time effective for its purpose. After unsatisfactory at- 

 tempts with various gelatinous solid media, with charcoal, etc., it was 

 decided that the commercial gray filter paper had more to recom- 

 mend it than any other substance suggested. Accordingly, all ex- 

 periments were made in Erlenmeyer flasks of 150 c. c. capacity, and 

 in each flask was placed about 6 grams of this paper wadded into 

 pellets. The latter was moistened in each case with the nutrient 

 solution used. The flasks were subsequently sterilized in the auto- 

 clave and then inoculated with a very minute fragment of straw 

 with the fresh mycelium from a pure culture on manure. 



Tabulation of special results. — In the following tables are given 

 the results of two out of several series of experiments, which have 

 been conducted in order to throw some light on the point just dis- 

 cussed. These tables include, also, many cultures on media of un- 

 known composition. ^ 



Table V. — Results of f/rowth on iiirdia — First series of experiments. 



No. 



Medium. 



Extent of growth. 



la 



lb 



2a 



2b 



3a 



3b 



4a 



4b 



5a 



5b 



6a 



6b 



7a 



7b 



8a 



8b 



Oa 



9b 



10a 



10b 



11a 



lib 



12a 



12b 



13a 



13b 



JDt. HoO - 



[solution A -- - - 



[■Solution A and cane sugar, li per cent 



■Cane sugar, l.j per cent : 



[solution A and lactose, IJ^ per cent _ - - . 



[Lactose, li per cent _ 



[solution A and glycerin, IJ per cent 



[Glycerin, 1^ percent 



[solution A and starch paste, i per cent . 



[starch paste, i per cent 



[Solution A and starch, i per cent, and diastase, trace 



[starch, i per cent, and diastase, trace 



I [solution A and dextrose, li per cent 



/Very slight, 

 t Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



fFair growth 

 1 Do. 



Do. 



Do. 



/Contaminated, discarded. 

 \Fair. 

 /Good, 

 t Do. 

 J Very slight. 

 iGood. 



