MR. W. WEST: ECOLOGICAL NOTES. 19 
A single very old Chestnut was examined, the main part of its trunk was 
almost covered with Opegrapha varia and Stereodon resupinatus, mixed with 
a little Homalia trichomanoides. A number of exposed Birches about 30 to 
35 centimetres in diameter showed that Parmelia saxatilis was the dominant 
epiphyte (30), with P. fuliginosa var. lwtevirens (10), a little Ævernia 
Prunastri, an interlacing of /sothecium myosuroides and Stereodon cupressi- 
forme mostly about the base (5), and sub-bareness (55). 
Near Bettws-y-Coed, epiphytes on Oaks, Birches, and Sycamores (see р. 80). 
Average rainfall, 53 inches ; average rainy days, 217. 
Among the above were smaller quantities of Lecanora subfusca, Cladonia 
fimbriata, С. pyæidata, Usnea ceratina, Graphis scripta, Dicranum scoparium, 
and surrounding the base of some was Leucobryum glaucum, climbing up 
from the ground. 
Average approximate percentages of the chief epiphytes on the above 
thirteen lots :—Stereodon cupressiformis 27, Parmelia saxatilis 10, Lecanora 
tartarea 84, Pertusaria spp. 34. 
Some other Oaks in the same wood were quite covered up to three metres 
with but little else than Stereodon cupressiformis, and above that with the 
following lichens mixed with it, and in about the same proportions collectively 
as the moss :—Parmelia saxatilis (10), P. fuliginosa var. letevirens (5), 
Platysma glaucum (5), Evernia Prunastri (2), Calicium sp. barren (a little), 
the rest being almost bare. 
A number of trees had been blown down, their branches were examined; 
the epiphytes were:—Parmelia saxatilis (15), P. physodes (10), P. fuli- 
ginosa var. letevirens (5), Evernia Prunastri (3), Usnea ceratina (3), Pyrenula 
nitida (3), and a few other crustaceous lichens ; sub-bareness (about 50). 
The undergrowth as seen in early June under the trees of this wood (Oak 
chiefly, with a few Picea excelsa, Larix europea, &c.), was a varied asso- 
ciation of Lonicera Periclymenum, Teucrium Scorodonia, Pteris (none at all 
in some places), Rubus sp., Anemone nemorosa, Ranunculus Ficaria, Lastræa 
Filiv-mas, and Endymion non-scriptum. Arum maculatum, Stellaria Holostea, 
and Hypericum рщейтит were scarce, the Ændymion was quite dominant 
here and there, and where rocks abutted, Cotyledon Umbilicus occurred. 
Between the above plants were masses of Hylocomium triquetrum, Thuidium 
tamariscinum, and Polytrichum formosum. 
At a considerable distance from the last wood, in an exposed position on a 
slope, a number of trees of Picea excelsa had been recently felled: their 
branches were examined, Parmelia physodes was the dominant epiphyte, it 
almost completely covered them. 
In the lower part of another wood, there was hardly any species of Ulota 
or Orthotrichum on the trees, and only fragmentary lichens, though the 
