236 
A (j. Tansley. 
lateness of the hour the cars were stopped about halfway and the 
party climbed the hillside and examined the vegetation of the 
limestone slopes, terraces and pavements, till the fall of dusk 
made it impossible to continue. One centre of interest was the 
occurrence of heath plants on the limestone. Calluna vulgaris, for 
instance, grows vigorously, with living functional roots pressed 
against the surface of the limestone rock. The ling does not, how¬ 
ever, grow alone in this position, but always in the midst of great 
clumps of mosses, in the humus formed by which its seedlings have 
probably germinated. There is a very extensive heath flora, which 
specially interested Professor Graebner, on these limestone terraces. 
The other point of interest was the vegetation of the limestone 
pavements and particularly of the great chemically eroded fissures 
which abound in them. Here many species of trees and shrubs 
grow luxuriantly, but very seldom project above the surface of the 
pavement. It was generally agreed that this Burren country, with its 
almost untouched vegetation presenting an abundance of problems, 
deserves very thorough ecological study, which could only be carried 
out by carefully planned co-operative work with a properly equipped 
field station. When dusk fell the party returned to the road and 
drove back to Ballyvaghan in a nearly saturated atmosphere which 
foretold a change in the weather. Heavy rain, the first (except for 
a few drops at Blakeney) that had been experienced during the tour, 
fell during the night, and for the remainder of the time spent in 
Ireland the weather was unsettled and wet. 
On the morning of August 24th some of the party visited before 
breakfast a fine area of Potentilla fruticosa, which is locally 
abundant in this region. After breakfast cars were taken for the 
drive to Ardrahan, entirely through the limestone country, with its 
regularly terraced hills and intervening stretches of plain. One of 
the most remarkable features of this highly glaciated region is the 
great scarcity of drift: where drift does occur it is at once recog¬ 
nisable by its different contours and the different vegetation which it 
bears. A short stop was made on the way to look at another piece 
of limestone pavement, but heavy rain drove the party back to the 
cars. After lunch at Ardrahan the train was taken for Limerick, 
Mallow and Killarney, which was reached late in the evening. 
On August 25th the party drove to the Upper Lake, where the 
morning was spent in the woods on the Old Red Sandstone dominated 
by Quercus sessiliflora, with Ilex Aquifoliuni specially abundant, and 
yew, birch, mountain ash and Salix cinerea. Besides the ground flora 
characteristic of Quercus sessiliflora woods, Saxifraga umbrosa and 
Euphorbia hiberua were conspicuous and abundant, and Melampyrum 
pratense var. Mans with its bright golden flowers and distinctly open 
palate was a beautiful feature. But the most interesting plant 
of all was, of course, Arbutus Unedo, which in spite of much des¬ 
truction in past times is still abundant and locally dominant in these 
woods. The great luxuriance of all the plants, the abundance of 
bryophytes and of plants growing epiphytically on the trees, 
especially Polypodium vulgare and Saxifraga umbrosa, were a dis¬ 
tinctive feature of the vegetation. Pinguicula grandiflora was 
gathered near the present upper limit of the woods, but Saxifraga 
Geum was not seen nor was the “Killarney Fern” ( Trichomanes 
