MR. W. H. BURRELL ON LEUCOBRYUM GLAUCUM, SCHP. 539 
habit of bud development combined with the power of 
retaining moisture under conditions which would place most 
mosses in a state of rest. is. I believe, a simple and sufficient 
explanation of the phenomenon. 
In looking round for a cause for such frequent disturbance 
as would reverse the tufts from time to time and enable the 
buds to develop in all directions, the tread of sportsmen and 
woodmen and other human agencies seemed insufficient, and 
I was led to consider game birds as a possible medium, by the 
fact that I have long been familiar with the sight of small 
tufts of other mosses lying about open heathland. For 
example, in dry exposed situations Dicranum scoparium forms 
large low mats which are often strewn with small tufts which 
I have assumed have been pulled out by pheasants in search 
of food ; the activity of these birds may be gauged by examin- 
ing a chestnut grove in winter ; torn and empty husks proclaim 
that the nuts have been consumed on the spot. It is worthy 
of note that the site at Aylmerton is under beech trees, whose 
fallen nuts would provide the necessary attraction. In large 
game may be found, I believe, an ever active and ever 
present source of disturbance ; scrapping for food they turn 
over the displaced tufts ; buds develop geotropically at 
whichever surface happens to be uppermost, giving rise to 
spheroidal cushions. 
