MR. W. H. BURRELL ON LEUCOBRYUM GLAUCUM, SCHP. 537 
V. 
NOTE ON A FORM OF 
LEUCOBRYUM GLAUCUM, SCHP. 
By W. H. Burrell, F.L.S. 
Read 2 8th January, i<)o8. 
In the second edition of Dixon and Jameson’s 1 Handbook 
of British Mosses,’ reference is made to a curious state of 
this plant collected by Miss C. M. (libbings at Hedsor, Bucks, 
in “ spheroidal balls or cushions, entirely unattached, con- 
sisting of stems radiating outwards from a central point and 
showing no lack of vigorous growth in spite of freedom from 
anything like attachment, which obviously must have lasted 
for a considerable period.” 
While walking through the woods at Aylmerton in the spring 
of 1907, I observed a considerable quantity of Lcucobryum 
showing a similar development, and it seems desirable not 
only to report a county station for this interesting departure 
from normal habit, but to venture an opinion as to the cause. 
The site is the slope of a hill under beech trees, where 
a considerable quantity of the moss occurs, showing inter- 
mediate stages between ordinary plano-convex cushions 
attached to the forest soil, and perfect unattached buttons 
with little or no distinction between upper and lower surfaces. 
The relation of some of the tufts to the substratum was 
instructive. I11 one case a tuft of almost perfect shape was 
adhering by radicles to a leaf of the previous year ; its attach- 
ment to a recently fallen leaf and the cleanliness of the under 
surface, which was barely distinguishable from the upper 
surface, assisted in forming an opinion as to its history. In 
another case a tuft was resting on a mat of Mnium hornum ; 
