МВ. W. WEST : ECOLOGICAL NOTES. 85 
50 centimetres from the base, above that were :—Parmelia physodes (10), 
P. saxatilis (3), Evernia Prunastri, and Opegrapha atra (a little), sub-bareness 
(about 85). The Larches had hardly anything on them except scattered 
plants of Parmela physodes, with a few small patches of Cladonia sp. near 
the base. 
Some Pines in Wastdale about 70 years old, at about 75 metres elevation, 
were quite without mosses or hepaticæ ; Parmelia physodes was dominant 
(50 to 60), P. sawatilis (8), the rest was almost bare, with the exception 
of about 3 per cent. of a mixture of P. caperata, Evernia furfuracea, 
Е. Prunastri, Usnea ceratina, and small patches of a Cladonia. 
GENERAL SUMMARY OF FOREGOING OBSERVATIONS. 
Summing up what can be chiefly gathered from the preceding tables, 
Stereodon cupressiformis var. filiformis (not in all cases the typical variety) 
is shown to be by far the most abundant epiphyte, Parmelia saxatilis coming 
next, often, but not always, the var. furfuracea. On subjecting the above 
tables to analysis, the percentage ratio (inter se) of the chief epiphytes comes 
out approximately as follows :—Stereodon cupressiformis 16, Parmelia saxa- 
tilis 6, lsothecium myosuroides 2, Frullania dilatata 2, Parmelia fuliginosa 
var. letevirens 2, Lecanora tartarea 2, Platysma glaucum 1, Pertusaria globu- 
lifera with P. faginea and other species 1. 
This summary is not by any means given as a decisive statement suitable 
to every district, or even for the average of several districts ; it represents 
approximately what was actually observed in those districts that were partly 
examined in some detail. Many uncommon epiphytes were noted which 
are not enumerated, as they only occurred either very locally or in very 
small quantity, the more frequent of them come under the category of 
* sub-bareness.” 
Frullania dilatata is sometimes a subdominant epiphyte. ^ Lobaria pul- 
monaria, Ricasolia letevirens, Nephromium lusitanicum, Lobarina scrobiculata, 
and some species of Parmelia and Cladonia often grow very extensively over 
the surface of Stereodon cupressiformis, as well as over the sub-bare bark. 
_ Pyrenula nitida sometimes almost covers young trees, especially those with 
а somewhat smooth bark. Opegrapha atra also often occupies considerable 
areas ; and Graphis elegans sometimes almost covers the Hollies. Parmelia 
caperata is here and there one of the chief epiphytes, especially near the 
sea. P. physodes in very exposed places, especially on Conifers, is sometimes 
the most abundant epiphyte. Now and then one finds Parmelia perlata or 
P. fuliginosa var. letevirens to be the chief corticolous lichen. Other 
epiphytic lichens, which are occasionally found in fair abundance, have not 
been mentioned, but these are often local, requiring special conditions, such 
as Alectoria jubata in montane and subalpine valleys. Metzgeria furcata 
is here and there in great profusion as an epiphyte, often creeping over 
foliaceous lichens ; and in moister western woods Radula complanata is also 
sometimes a conspicuous epiphyte. 
