GERMINATION STUDIES. 



15 



inof sfermination bv chemical stimuli. In distilled water, on the one 

 hand, and in plant decoctions (such as decoctions of beans, sugar 

 beets, mushrooms, potatoes, etc.) and in bouillon, on the other hand, 

 there have been tested a large number of inorganic and organic salts, 

 carbohydrates, nitrogenous compounds, and active enzymes. 



The results of one series of experiments are tabulated in detail. 

 In g(nieral, it has been found that dulcite, monobasic magnesium 

 phosphate, magnesium phosphite, magnesium potassium ammonium 

 phosphate, ammonium molybdate, magnesium lactophosphate, dibasic 

 calcium phosphate, and other salts, especially phosphates, have in one 

 medium or another been more or less effective as stimuli for germina- 

 tion. Unfortunately, none of the substances mentioned, apparently, 

 are very strong stimuli ; they are unable to cause invariable germina- 

 tion in all nutrient media. Moreover, in subsequent series, where the 

 conditions have been the same, within experimental possibilities, 

 wholly analogous results have not always been obtained. No account 

 lias been taken, however, of the particular variety of Agaricus cam- 

 pestris from which the spores were obtained, and it may be that this 

 will influence the results. 



It is to be noted from the following table that Miss Ferguson's 

 method of employing living bits of mycelium was modified by the use 

 of small pieces of the inner tissue of a young mushroom taken under 

 sterile conditions. It was found that often a new growth of mycelium 

 was developed from this tissue. Whenever this growth appeared, 

 the influence upon spores in the drop culture was, as might be 

 expected, the same as had been demonstrated for the living mycelium. 

 Frequently a few spores germinated within from three to five days. 

 The most interesting conclusion, however, which could be draAvn from 

 the cultures in which small bits of tissue were used was the following: 

 Under favorable conditions a small piece of the inner growing tissue 

 of a mushroom is capable of producing a mycelium with great readi- 

 ness. This fact has been utilized, as shown in detail later, in the 

 development of a new and effective method of securing pure cultures 

 of fleshy fungi in general. 



Table I. — Extent of germination. 



6329— No. 85—05 m- 



