PTILIDIUM PULCHERRIMUM (WEB), HAMPE, 
IN EPPING FOREST. 
By JOSEPH ROSS. 
[Read 24 th February 1917.] 
HE distribution of this liverwort is said, in MacVicar’s 
JL Handbook of British Hepatics (1912), to be from Derby to 
Aberdeen, and the plant is termed “ rare.” Mr. W. R. Sherrin 
tells me that it is recorded from South Somerset. Mr. \Y. E. 
Nicholson, of Lewes, published in the last issue of the South 
Eastern Naturalist a long (and clearly a complete) list of the 
hepatics of the Tunbridge Wells district. In that list, P. 
pulcherrimum does not appear, though P. ciliare, the allied 
species, is included. 
Authorities differ as to whether P. pulcherrimum is a dis¬ 
tinct species or a variety of P. ciliare. The usual habitats of 
the two plants are distinctive. P. ciliare is usually found on 
wet moors : P. pulcherrimum on trunks of trees or about their 
roots ; but neither is confined to such situations. I have 
•assumed that P. pulcherrimum is a definite species, but I have 
not yet found P. ciliare growing. 
P. pulcherrimum occurs on an oak not far from Cuckoo Pits, 
a well-known area in the Chingford part of Epping Forest. 
Map C in Mr. E. N. Buxton’s Guide calls the locality Pear Tree 
Plain. The oak is on the London clay, but bracken grows freely 
at a short distance, and this may indicate the existence of gravel. 
On the higher parts south and east, there are numerous evidences 
of gravel digging. South of the spot where the oak grows is a 
small open plain, marshy in winter ; and possibly this is actually 
the Pear Tree Plain of Mr. Buxton’s map. Two tracks lead 
north from the plain, and these become water-logged on the 
least provocation, for the area is distinctly damp. 
The oak on which P. pulcherrimum occurs is a few yards 
west of one of the tracks, and leans in a pronounced degree to 
the south. It is on the north side of the tree that the plant 
grows. This is what one would expect ; for the northern side 
is protected from the drift of London’s smoke. At its base, 
the trunk of the tree rises at an angle of about 75 degrees, and 
four or five feet from the ground the angle is increased to about 
45 degrees. The Piilidium grows from about i| feet from the 
