CHAPTER II. 
PLANTS SPREAD BY MEANS OF ROOTS. 
3. Fairy rings. — Several low forms of plant life, such 
as Marasmius oreades, Spatliularia jlavida, and some of the 
puffballs, start in isolated spots in the grass of a lawn or 
pasture, and spread each year from a few inches to a foot 
or more in every direction, usually in the form of a circle ; 
at the end of fifteen years some of these circles acquire 
a diameter of fifteen to twenty feet or more. These are 
known as fairy rings. Before science dispelled the illusion 
they were believed to have been the work of witches, 
elves, or evil spirits, from which arose the name. 
Several kinds of lichens and mosses and the like, grow- 
ing on the barks of trees, fence boards, and low ground, 
spread slowly in the manner of fairy rings. 
However, the spreading is not always a slow, creeping 
process, for sometimes these low plants spread over an 
incredible distance in a short space of time. In some 
instances they appear suddenly almost anywhere, and at 
any season of the year. They are all minute and exist 
in countless numbers, and their devices for securing wide 
dispersion are so various as to entitle them to first rank 
in this respect. Some send off spores with a sharp puff, 
as if shot from a little gun. Some of these spores float 
