ECOLOGY OF FUNGI 47 



continuously moist, warm summer; nevertheless, when such 

 conditions are forthcoming, our open pastures and moorlands are 

 studded with some amongst the most beautiful of our agarics. 



This suggests the question as to how those pasture-loving fungi 

 tide over the time between one favourable season and another, the 

 interval being often of many years' duration. The answer is not 

 forthcoming at present. Uo the spores remain in a dormant con- 

 dition until a genial season arrives ? Or do the spores germinate at 

 once, and form a mycelium which possesses the power of remaining 

 in a vegetative condition in the soil, obtaining its food from humus, 

 etc., until conditions favour the development of a sporophore ? 



It has been suggested that the appearance of certain species is 

 })eriodical and fixed, say at periods of three years, etc. Careful 

 observations extending over several years, and conducted in different 

 parts of the country, would test the value of this observation, and 

 are certainly worth trying. The areas selected should preferably be 

 located in mixed woods, where the different species of fungi occur in 

 much greater abundance than in pure woods, or those consisting of 

 one kind of tree only. There should be an absence of bracken, dogs' 

 mercury, etc. Points that would have to be attended to are, the 

 kinds of trees present, aspect of tlie area, amount of natural drain- 

 age, annual temperature and rainfall, amount of humus and nature 

 of soil, and perhaps also the soil temperature. Work of this nature 

 implies the co-operation of several independent workers. The 

 greater the number the better the results. 



The following idea may perhaps be worth considering, so far as 

 the gill-bearing fungi are concerned. As the reader will learn, 

 farther on in this book, the agarics or gill-bearing fungi are divided 

 into four primary groups, depending on the colour of the mature 

 spores (all spores are colourless when young). The most primitive 

 group, in time, is black or purple-spored. From these evolved the 

 brown-spored group, which in turn gave origin to the group having 

 pink spores. From this group evolved the white-spored section, 

 the most modern in point of time. Structurally, from the point 

 of spore dispersion, and in many physiological features, as the 

 presence of poisons, alkaloids, etc., there is a gradual sequence of 

 development , from the black-spored group to that producing white 

 spores. 



It is a fact well known to growers of mushrooms, that the beds 

 are often overrun by other worthless kinds of fungi, but in every 

 instance the intruders liave been higher in the sequence of evolution 

 than the dark-spored mushroom group. In other words, the stray 

 mushrooms infesting tlie mushroom beds always have pink or white 

 spores. It is well known that the roots of certain flowering plants 

 give off substances inimical to other plants, which consequently 

 cannot grow in their neighbourhood. My observations lead me 

 to believe that in a similar manner the mycelium of one fungus can 



