368 
THE PRINCIPLES OP BOTANY. 
room ” (Agaricus gambosus), from tlie larger circle, while, in 
tlie summer, the brown ring of the smaller circle will be 
occupied by the “ Champignon ” (Agaricus oreades). There 
are other rings on the farm occupied in their turn with 
Agaricus arvensis , our larger catsup mushroom, the A. per- 
sonals, “ blewits,” and other “ fairy ring species.” Some- 
times the same ring will produce most, if not all, of these 
species at different times. 
We have here, then, to consider the important fact, which 
has been hitherto overlooked, that fairy rings either may or 
may not be occupied by fungi, and hence, then, the theory 
that the rings are caused by them, to say the least, is not 
always true. 
That fungi are the usual accompaniments of fairy rings is 
quite true ; but, as we shall ultimately determine, these are the 
results of the circumstances by which such rings are formed, 
and not the real cause of all the phenomena which we have 
observed. 
Still, that such conspicuous objects as the Agarics we have 
named are common to these rings is certain, and there is no 
wonder then that different writers, in explaining the facts, 
should always refer to the fungi as the true cause of the ring, 
though, at the same time, this wrong assumption has, as we 
think, been the source of grave errors in the conclusions 
arrived at. Thus Professor Way, in a paper on the f Fairy 
Pings of Pastures/ in vol. 7 of the f Journal of the Poyal 
Agricultural Society/ offers the following remarks : — 
“ Omitting the consideration of the many theories which 
have been offered in explanation of these curious rings, I 
shall only remark that by far the most scientific and intelli- 
gible solution of the question is that which was based upon 
De Candolle’s theory of excretion of plants. It was supposed 
that, from one cause or another, the germ of a fungus or 
agaric became deposited on some point of a piece of pasture 
land ; that the fungus formed from it, after passing through 
the various stages of its growth, shed its seeds or sporules 
necessarily in a circle exterior to its point of connection with 
the ground, and that, in the following season, a series of 
these plants was produced in the form of a small circle. 
This new crop would, in its turn, come to maturity, shedding 
seeds both towards the centre and on the outside of the ring. 
Were circumstances favorable to the development of the 
seeds deposited on the inside of the ring, the diameter of it 
might increase indeed, but it would have the form, not of a 
ring with an open centre, but of a flat disc. This, however, 
does not take place ; the fungi of one year are replaced in 
